diff --git a/frontend/src/lib/components/DateTimeInput.svelte b/frontend/src/lib/components/DateTimeInput.svelte
index ac95a1a566..55e1dbc0e1 100644
--- a/frontend/src/lib/components/DateTimeInput.svelte
+++ b/frontend/src/lib/components/DateTimeInput.svelte
@@ -8,6 +8,7 @@
 	import { twMerge } from 'tailwind-merge'
 	import { createDispatcherIfMounted } from '$lib/createDispatcherIfMounted'
 	import TextInput from './text_input/TextInput.svelte'
+	import { parseDateTime } from './dateTimeInput'
 	// import ToggleButtonGroup from './common/toggleButton-v2/ToggleButtonGroup.svelte'
 
 	interface Props {
@@ -45,7 +46,7 @@
 	// let format: 'local' | 'utc' = 'local'
 
 	function parseValue(value: string | null | undefined = undefined) {
-		let dateFromValue: Date | undefined = value ? new Date(value) : undefined
+		let dateFromValue: Date | undefined = value ? parseDateTime(value, timezone) : undefined
 		if (!isValidDate(dateFromValue)) {
 			date = undefined
 			time = '12:00'
diff --git a/frontend/src/lib/components/dateTimeInput.test.ts b/frontend/src/lib/components/dateTimeInput.test.ts
new file mode 100644
index 0000000000..8a466ee5cf
--- /dev/null
+++ b/frontend/src/lib/components/dateTimeInput.test.ts
@@ -0,0 +1,14 @@
+import { expect, it } from 'vitest'
+import { parseDateTime } from './dateTimeInput'
+
+it('reads a zone-less naive value as its digits, outside UTC too', () => {
+	const tz = process.env.TZ
+	process.env.TZ = 'Europe/Paris'
+	try {
+		expect(parseDateTime('2027-09-09T10:00', 'naive').getUTCHours()).toBe(10)
+		expect(parseDateTime('2027-09-09T10:00', 'local').getUTCHours()).toBe(8)
+	} finally {
+		if (tz === undefined) delete process.env.TZ
+		else process.env.TZ = tz
+	}
+})
diff --git a/frontend/src/lib/components/dateTimeInput.ts b/frontend/src/lib/components/dateTimeInput.ts
new file mode 100644
index 0000000000..7ed8517321
--- /dev/null
+++ b/frontend/src/lib/components/dateTimeInput.ts
@@ -0,0 +1,5 @@
+/** A naive value's digits are its time: `Date` would read a zone-less date-time as local time */
+export function parseDateTime(value: string, timezone: 'naive' | 'local'): Date {
+	const zoneless = /^\d{4}-\d{2}-\d{2}[T ]\d{2}:\d{2}(:\d{2}(\.\d+)?)?$/.test(value)
+	return new Date(timezone === 'naive' && zoneless ? value.replace(' ', 'T') + 'Z' : value)
+}
diff --git a/frontend/src/lib/components/triggers/schedules/ScheduleEditorInner.svelte b/frontend/src/lib/components/triggers/schedules/ScheduleEditorInner.svelte
index df09a81671..48227dea44 100644
--- a/frontend/src/lib/components/triggers/schedules/ScheduleEditorInner.svelte
+++ b/frontend/src/lib/components/triggers/schedules/ScheduleEditorInner.svelte
@@ -103,7 +103,7 @@
 	let loading = $state(false)
 	let drawerLoading = $state(true)
 	let showLoading = $state(false)
-	let initialConfig: Record<string, any> | undefined = undefined
+	let initialConfig = $state<Record<string, any> | undefined>(undefined)
 	let extraPerms: Record<string, boolean> = $state({})
 	// Path the permissions above were loaded for — the verdict is about the schedule as
 	// stored, not about a rename being typed into the form. `undefined` until a config has
@@ -281,7 +281,7 @@
 			schedule = s?.schedule ?? '0 0 12 * *'
 			initialSchedule = schedule
 			timezone = s?.timezone ?? Intl.DateTimeFormat().resolvedOptions().timeZone
-			paused_until = s?.paused_until ?? undefined
+			paused_until = asPicked(s?.paused_until)
 			showPauseUntil = paused_until !== undefined
 			summary = s?.summary ?? ''
 			labels = s?.labels ?? undefined
@@ -372,6 +372,12 @@
 		}
 	}
 
+	// The draft check compares as text and the picker writes `.000Z`: spell the stored time
+	// the same, or a time changed and changed back reads as unsaved (`…:00Z` vs `…:00.000Z`).
+	function asPicked(time: string | null | undefined): string | undefined {
+		return time ? new Date(time).toISOString() : undefined
+	}
+
 	async function loadScheduleCfg(cfg: Record<string, any>): Promise<void> {
 		loading = true
 
@@ -382,7 +388,7 @@
 		schedule = cfg.schedule
 		initialSchedule = schedule
 		timezone = cfg.timezone
-		paused_until = cfg.paused_until
+		paused_until = asPicked(cfg.paused_until)
 		showPauseUntil = paused_until !== undefined
 		summary = cfg.summary ?? ''
 		labels = cfg.labels ?? undefined
diff --git a/frontend/src/lib/components/triggers/useTriggerDraftSync.svelte.ts b/frontend/src/lib/components/triggers/useTriggerDraftSync.svelte.ts
index abe2e287bd..daaab5a6f5 100644
--- a/frontend/src/lib/components/triggers/useTriggerDraftSync.svelte.ts
+++ b/frontend/src/lib/components/triggers/useTriggerDraftSync.svelte.ts
@@ -47,6 +47,8 @@ export interface TriggerDraftSyncOptions {
 	/**
 	 * The deployed baseline the editor's dirty check compares against —
 	 * `originalConfig` for TriggerCrud editors, `initialConfig` for Schedule.
+	 * Must read `$state`: the baseline is cached, so a plain `let` set by a later
+	 * open stays stale and the "unsaved changes" banner never shows.
 	 */
 	deployed: () => Cfg | undefined
 }
@@ -61,8 +63,8 @@ export interface TriggerDraftSync {
 	 */
 	readonly hasDraft: boolean
 	/**
-	 * Whether a deployed baseline exists (banner can appear). Reactive, unlike
-	 * reading `deployed` directly (a plain `let`), so callers can reserve its slot.
+	 * Whether a deployed baseline exists (banner can appear), so callers can
+	 * reserve its slot.
 	 */
 	readonly hasBaseline: boolean
 	/** The deployed baseline the dirty check compares against. */
@@ -172,8 +174,7 @@ export function useTriggerDraftSync(opts: TriggerDraftSyncOptions): TriggerDraft
 		!opts.drawerLoading() && baseline != null && cfgDiffers(opts.getCfg() as Cfg, baseline as Cfg)
 	)
 
-	// Reactive "banner is possible" — depends on `drawerLoading()` so it
-	// re-evaluates (and re-reads the plain-`let` baseline) once the load settles.
+	// "Banner is possible" — false until the load settles.
 	const hasBaseline = $derived(!opts.drawerLoading() && opts.deployed() != null)
 
 	/** `auto: true` marks a discard from the reactive persist-effect (not an
@@ -313,8 +314,7 @@ export function useTriggerDraftSync(opts: TriggerDraftSyncOptions): TriggerDraft
 			const deployed = opts.deployed()
 			if (deployed == null) return
 			// The deployed object too, so `resetToDeployed` restores the new value;
-			// `settledBaseline` because it shadows the deployed object and is the
-			// reactive side (an editor's `deployed` may be a plain `let`).
+			// `settledBaseline` because it shadows the deployed object.
 			Object.assign(deployed, patch)
 			settledBaseline = { ...snapshotCfg(settledBaseline ?? deployed), ...patch }
 		}