diff --git a/src/common/query/src/series_frame/tests.rs b/src/common/query/src/series_frame/tests.rs
index aeb0fbdeb8f..e77f93e0778 100644
--- a/src/common/query/src/series_frame/tests.rs
+++ b/src/common/query/src/series_frame/tests.rs
@@ -2606,7 +2606,7 @@ async fn interleaved_constructors_accept_without_polling() {
 /// The unpack stream rejects a batch whose schema differs from the stream's declared schema,
 /// including drift in metadata the codec itself does not interpret and an empty batch that
 /// carries the drift; the reserved layout metadata is rejected as well. Since the current layout is
-/// `v2`, the drift case rewrites the layout to `v1`: any value other than this revision's is refused,
+/// `v1`, the drift case rewrites the layout to `v2`: any value other than this revision's is refused,
 /// so a stale or a future spelling cannot be decoded under the current columns.
 #[tokio::test]
 async fn unpack_rejects_unrelated_metadata_drift_and_empty_schema_changes() {
@@ -2626,9 +2626,9 @@ async fn unpack_rejects_unrelated_metadata_drift_and_empty_schema_changes() {
 
     let mut unrelated = base.metadata().clone();
     unrelated.insert("app.unrelated".into(), "x".into());
-    // The current layout is `v2`, so a frame that still declares `v1` is the drift here.
+    // The current layout is `v1`, so a frame that declares `v2` is the drift here.
     let mut reserved = base.metadata().clone();
-    reserved.insert("greptime.series.layout".into(), "v1".into());
+    reserved.insert("greptime.series.layout".into(), "v2".into());
     let mut renamed = base.metadata().clone();
     renamed.insert("app.renamed".into(), "y".into());
     let mut different_ordering = base.metadata().clone();
@@ -2696,7 +2696,7 @@ fn raw_series_ordering_metadata_fixture() {
     }
 
     let cases: Vec<Case> = serde_json::from_str(include_str!(
-        "../../../../../tests/compatibility/wire/raw_series_ordering/v2_metadata.json"
+        "../../../../../tests/compatibility/wire/raw_series_ordering/v1_metadata.json"
     ))
     .unwrap();
     for case in cases {
@@ -3286,11 +3286,11 @@ async fn unpack_reports_the_ordering_the_frame_declares() {
 
 /// Reserved layout metadata this revision does not write is rejected instead of being read as the
 /// current layout, so a frame cannot be decoded under a contract it did not declare. The current
-/// layout is `v2`; a `v1` frame and every unknown value are refused alike.
+/// layout is `v1`; a `v2` frame and every unknown value are refused alike.
 #[tokio::test]
 async fn unpack_rejects_unknown_layout_metadata() {
     let cases = [
-        ("greptime.series.layout", "v1"),
+        ("greptime.series.layout", "v2"),
         ("greptime.series.layout", "v3"),
         ("greptime.series.content", "series"),
         ("greptime.series.time", "timestamps_v2"),
diff --git a/src/datatypes/src/series/frame.rs b/src/datatypes/src/series/frame.rs
index c253c262cdb..559294b4023 100644
--- a/src/datatypes/src/series/frame.rs
+++ b/src/datatypes/src/series/frame.rs
@@ -33,9 +33,10 @@
 //! Packing accumulates bounded multi-row batches: [`SeriesFrameCursor`] walks one validated chunk
 //! and [`SeriesFrameBuilder`] emits rows directly as Arrow arrays once a row or estimated byte bound
 //! is reached. Decoding reuses one prepared
-//! schema per stream through [`SeriesFrameDecoder`]. The column layout and existing metadata stay
-//! on the `v2` contract. Raw frames may also declare `greptime.series.ordering=interleaved`; older
-//! readers that do not recognize this ordering reject it. A key-encoded frame declares a versioned
+//! schema per stream through [`SeriesFrameDecoder`]. Column layout, metadata, and wire strings stay
+//! on the single `v1` contract. Raw frames may also declare `greptime.series.ordering=interleaved`;
+//! older readers that do not recognize this ordering reject it. A key-encoded frame declares a
+//! versioned
 //! [`LabelDecodeSpec`] so its labels can be decoded from the received schema alone, and an evaluated
 //! frame declares its [`GridSpec`] once instead of repeating timestamps.
 //!
@@ -130,12 +131,14 @@ const RESERVED_KEYS: [&str; 9] = [
     AGGREGATE_COMPONENTS,
 ];
 
-/// The only layout this revision writes and reads.
+/// The layout marker every frame this engine writes carries.
 ///
-/// A frame declaring any other value is refused instead of decoded: the sample representation of an
-/// unreleased format is not worth a second decoder, and silently guessing would turn a format change
-/// into wrong values.
-pub const FRAME_LAYOUT_VERSION: &str = "v2";
+/// It stays at one value: the frame is the native path's internal transport and has never shipped,
+/// so there is no released layout to tell apart from this one. A reader that meets another marker
+/// refuses the frame instead of guessing at it - the check is what turns a stale producer into an
+/// error rather than into wrong values - but the marker itself does not move when the layout
+/// changes, because two binaries of one workspace are built from one revision.
+pub const FRAME_LAYOUT_VERSION: &str = "v1";
 
 /// Version of the label decode description this revision writes and reads.
 ///
diff --git a/src/datatypes/src/series/frame/tests.rs b/src/datatypes/src/series/frame/tests.rs
index 04a212c527a..d57353929a6 100644
--- a/src/datatypes/src/series/frame/tests.rs
+++ b/src/datatypes/src/series/frame/tests.rs
@@ -582,7 +582,7 @@ fn schema_and_key_explicit_round_trips_preserve_identity_and_bits() {
         .into(),
     );
     let mut expected_key_metadata = std::collections::HashMap::new();
-    expected_key_metadata.insert("greptime.series.layout".to_string(), "v2".to_string());
+    expected_key_metadata.insert("greptime.series.layout".to_string(), "v1".to_string());
     expected_key_metadata.insert("greptime.series.content".to_string(), "raw".to_string());
     expected_key_metadata.insert("greptime.series.labels".to_string(), "key".to_string());
     expected_key_metadata.insert("greptime.series.time".to_string(), "timestamps".to_string());
@@ -2061,9 +2061,9 @@ fn rejects_invalid_schema_and_metadata_and_accepts_valid_empty() {
         let mut metadata = valid.schema().metadata().clone();
         match metadata_case {
             "wrong_layout" => {
-                // `v2` is the only layout this revision reads, so the previously unreadable `v1`
-                // is what a wrong layout is spelled as now.
-                metadata.insert("greptime.series.layout".to_string(), "v1".to_string());
+                // `v1` is the only layout this revision reads, so `v2` is what a wrong layout is
+                // spelled as now.
+                metadata.insert("greptime.series.layout".to_string(), "v2".to_string());
             }
             "wrong_labels" => {
                 metadata.insert("greptime.series.labels".to_string(), "explicit".to_string());
@@ -3390,7 +3390,7 @@ fn cross_chunk_rows_coalesce_into_one_multirow_batch() {
         ["read_key", "is_last", "time", "fields"]
     );
     for (key, value) in [
-        ("greptime.series.layout", "v2"),
+        ("greptime.series.layout", "v1"),
         ("greptime.series.content", "raw"),
         ("greptime.series.labels", "key"),
         ("greptime.series.time", "timestamps"),
@@ -4039,8 +4039,8 @@ fn decoder_reuses_cached_schema_and_rejects_schema_evolution() {
 
     // Reserved metadata and evolved fields are rejected, including by a zero-row batch.
     for (key, value) in [
-        // `v2` is the layout this decoder expects, so the unreadable `v1` is the wrong one.
-        ("greptime.series.layout", "v1"),
+        // `v1` is the layout this decoder expects, so `v2` is the wrong one.
+        ("greptime.series.layout", "v2"),
         ("greptime.series.content", "evaluated"),
         ("greptime.series.labels", "explicit"),
         ("greptime.series.time", "grid"),
@@ -4229,7 +4229,7 @@ fn schema_with_metadata(metadata: Vec<(String, String)>) -> Schema {
 /// The five metadata entries every raw v2 frame declares, with the given label mode.
 fn base_metadata(labels: &str) -> Vec<(String, String)> {
     [
-        ("greptime.series.layout", "v2"),
+        ("greptime.series.layout", "v1"),
         ("greptime.series.content", "raw"),
         ("greptime.series.labels", labels),
         ("greptime.series.time", "timestamps"),
@@ -4305,7 +4305,7 @@ fn raw_series_label_decode_metadata_fixture() {
     }
 
     let cases: Vec<Case> = serde_json::from_str(include_str!(
-        "../../../../../tests/compatibility/wire/raw_series_label_decode/v2_metadata.json"
+        "../../../../../tests/compatibility/wire/raw_series_label_decode/v1_metadata.json"
     ))
     .unwrap();
     for case in cases {
diff --git a/tests/compatibility/wire/raw_series_label_decode/v2_metadata.json b/tests/compatibility/wire/raw_series_label_decode/v1_metadata.json
similarity index 94%
rename from tests/compatibility/wire/raw_series_label_decode/v2_metadata.json
rename to tests/compatibility/wire/raw_series_label_decode/v1_metadata.json
index 43ded1e4bf6..3adabb36bd1 100644
--- a/tests/compatibility/wire/raw_series_label_decode/v2_metadata.json
+++ b/tests/compatibility/wire/raw_series_label_decode/v1_metadata.json
@@ -2,7 +2,7 @@
   {
     "name": "key_frame_declares_dense_description",
     "metadata": {
-      "greptime.series.layout": "v2",
+      "greptime.series.layout": "v1",
       "greptime.series.content": "raw",
       "greptime.series.labels": "key",
       "greptime.series.time": "timestamps",
@@ -14,7 +14,7 @@
   {
     "name": "key_frame_declares_sparse_description",
     "metadata": {
-      "greptime.series.layout": "v2",
+      "greptime.series.layout": "v1",
       "greptime.series.content": "raw",
       "greptime.series.labels": "key",
       "greptime.series.time": "timestamps",
@@ -26,7 +26,7 @@
   {
     "name": "missing_description_rejected",
     "metadata": {
-      "greptime.series.layout": "v2",
+      "greptime.series.layout": "v1",
       "greptime.series.content": "raw",
       "greptime.series.labels": "key",
       "greptime.series.time": "timestamps",
@@ -37,7 +37,7 @@
   {
     "name": "unknown_version_rejected",
     "metadata": {
-      "greptime.series.layout": "v2",
+      "greptime.series.layout": "v1",
       "greptime.series.content": "raw",
       "greptime.series.labels": "key",
       "greptime.series.time": "timestamps",
@@ -49,7 +49,7 @@
   {
     "name": "missing_field_rejected",
     "metadata": {
-      "greptime.series.layout": "v2",
+      "greptime.series.layout": "v1",
       "greptime.series.content": "raw",
       "greptime.series.labels": "key",
       "greptime.series.time": "timestamps",
@@ -61,7 +61,7 @@
   {
     "name": "unknown_field_rejected",
     "metadata": {
-      "greptime.series.layout": "v2",
+      "greptime.series.layout": "v1",
       "greptime.series.content": "raw",
       "greptime.series.labels": "key",
       "greptime.series.time": "timestamps",
@@ -73,7 +73,7 @@
   {
     "name": "wrong_field_type_rejected",
     "metadata": {
-      "greptime.series.layout": "v2",
+      "greptime.series.layout": "v1",
       "greptime.series.content": "raw",
       "greptime.series.labels": "key",
       "greptime.series.time": "timestamps",
@@ -85,7 +85,7 @@
   {
     "name": "unlisted_logical_tag_rejected",
     "metadata": {
-      "greptime.series.layout": "v2",
+      "greptime.series.layout": "v1",
       "greptime.series.content": "raw",
       "greptime.series.labels": "key",
       "greptime.series.time": "timestamps",
@@ -97,7 +97,7 @@
   {
     "name": "explicit_frame_with_description_rejected",
     "metadata": {
-      "greptime.series.layout": "v2",
+      "greptime.series.layout": "v1",
       "greptime.series.content": "raw",
       "greptime.series.labels": "explicit",
       "greptime.series.time": "timestamps",
@@ -109,7 +109,7 @@
   {
     "name": "malformed_json_rejected",
     "metadata": {
-      "greptime.series.layout": "v2",
+      "greptime.series.layout": "v1",
       "greptime.series.content": "raw",
       "greptime.series.labels": "key",
       "greptime.series.time": "timestamps",
@@ -121,7 +121,7 @@
   {
     "name": "wrong_layout_rejected",
     "metadata": {
-      "greptime.series.layout": "v3",
+      "greptime.series.layout": "v2",
       "greptime.series.content": "raw",
       "greptime.series.labels": "key",
       "greptime.series.time": "timestamps",
@@ -133,7 +133,7 @@
   {
     "name": "unregistered_reserved_metadata_rejected",
     "metadata": {
-      "greptime.series.layout": "v2",
+      "greptime.series.layout": "v1",
       "greptime.series.content": "raw",
       "greptime.series.labels": "key",
       "greptime.series.time": "timestamps",
@@ -146,7 +146,7 @@
   {
     "name": "evaluated_with_timestamps_rejected",
     "metadata": {
-      "greptime.series.layout": "v2",
+      "greptime.series.layout": "v1",
       "greptime.series.content": "evaluated",
       "greptime.series.labels": "explicit",
       "greptime.series.time": "timestamps",
@@ -158,7 +158,7 @@
   {
     "name": "evaluated_with_key_labels_rejected",
     "metadata": {
-      "greptime.series.layout": "v2",
+      "greptime.series.layout": "v1",
       "greptime.series.content": "evaluated",
       "greptime.series.labels": "key",
       "greptime.series.time": "grid_spans",
@@ -171,7 +171,7 @@
   {
     "name": "raw_with_grid_rejected",
     "metadata": {
-      "greptime.series.layout": "v2",
+      "greptime.series.layout": "v1",
       "greptime.series.content": "raw",
       "greptime.series.labels": "explicit",
       "greptime.series.time": "timestamps",
diff --git a/tests/compatibility/wire/raw_series_ordering/README.md b/tests/compatibility/wire/raw_series_ordering/README.md
index ce54838048a..a80c7f8f2da 100644
--- a/tests/compatibility/wire/raw_series_ordering/README.md
+++ b/tests/compatibility/wire/raw_series_ordering/README.md
@@ -1,7 +1,7 @@
 # Raw-series ordering schema metadata compatibility
 
-`v2_metadata.json` is a hand-authored, frozen set of Arrow schema metadata maps
-for the v2 series frame. It records the established layout/content/labels/time
+`v1_metadata.json` is a hand-authored, frozen set of Arrow schema metadata maps
+for the series frame, whose layout marker is the single `v1` this engine writes. It records the established layout/content/labels/time
 metadata and mandatory ordering entry, for raw frames and for evaluated ones.
 The Rust unit test parses these literal maps through `series_frame_ordering` and
 through `SeriesFrameDeclaration::parse`; the fixture is not produced by the
@@ -17,7 +17,7 @@ cargo nextest run -p common-query -E 'test(series_frame)'
 
 The fixture proves that missing ordering metadata and unknown values are rejected,
 the two original values decode, and that a whole declaration is accepted or
-refused consistently with its layout and content: a `v3` layout, an unregistered
+refused consistently with its layout and content: a `v2` layout, an unregistered
 `greptime.series.*` key, a raw frame that declares a grid, and any content/time or
 content/labels contradiction are refusals. Evaluated declarations use explicit
 `contiguous` ordering; streaming round trips for evaluated frames are covered by
diff --git a/tests/compatibility/wire/raw_series_ordering/v2_metadata.json b/tests/compatibility/wire/raw_series_ordering/v1_metadata.json
similarity index 91%
rename from tests/compatibility/wire/raw_series_ordering/v2_metadata.json
rename to tests/compatibility/wire/raw_series_ordering/v1_metadata.json
index 4b01c12091d..fced5bbbcb9 100644
--- a/tests/compatibility/wire/raw_series_ordering/v2_metadata.json
+++ b/tests/compatibility/wire/raw_series_ordering/v1_metadata.json
@@ -2,7 +2,7 @@
   {
     "name": "missing_ordering_rejected",
     "metadata": {
-      "greptime.series.layout": "v2",
+      "greptime.series.layout": "v1",
       "greptime.series.content": "raw",
       "greptime.series.labels": "explicit",
       "greptime.series.time": "timestamps"
@@ -13,7 +13,7 @@
   {
     "name": "known_contiguous",
     "metadata": {
-      "greptime.series.layout": "v2",
+      "greptime.series.layout": "v1",
       "greptime.series.content": "raw",
       "greptime.series.labels": "explicit",
       "greptime.series.time": "timestamps",
@@ -25,7 +25,7 @@
   {
     "name": "known_read_key_then_time",
     "metadata": {
-      "greptime.series.layout": "v2",
+      "greptime.series.layout": "v1",
       "greptime.series.content": "raw",
       "greptime.series.labels": "explicit",
       "greptime.series.time": "timestamps",
@@ -37,7 +37,7 @@
   {
     "name": "unknown_ordering_rejected",
     "metadata": {
-      "greptime.series.layout": "v2",
+      "greptime.series.layout": "v1",
       "greptime.series.content": "raw",
       "greptime.series.labels": "explicit",
       "greptime.series.time": "timestamps",
@@ -49,7 +49,7 @@
   {
     "name": "evaluated_contiguous",
     "metadata": {
-      "greptime.series.layout": "v2",
+      "greptime.series.layout": "v1",
       "greptime.series.content": "evaluated",
       "greptime.series.labels": "explicit",
       "greptime.series.time": "grid_spans",
@@ -62,7 +62,7 @@
   {
     "name": "evaluated_read_key_then_time_rejected",
     "metadata": {
-      "greptime.series.layout": "v2",
+      "greptime.series.layout": "v1",
       "greptime.series.content": "evaluated",
       "greptime.series.labels": "explicit",
       "greptime.series.time": "grid_spans",
@@ -75,7 +75,7 @@
   {
     "name": "wrong_layout_rejected",
     "metadata": {
-      "greptime.series.layout": "v3",
+      "greptime.series.layout": "v2",
       "greptime.series.content": "raw",
       "greptime.series.labels": "explicit",
       "greptime.series.time": "timestamps",
@@ -87,7 +87,7 @@
   {
     "name": "unregistered_reserved_metadata_rejected",
     "metadata": {
-      "greptime.series.layout": "v2",
+      "greptime.series.layout": "v1",
       "greptime.series.content": "raw",
       "greptime.series.labels": "explicit",
       "greptime.series.time": "timestamps",