diff --git a/test/e2e/instance-metrics.e2e.ts b/test/e2e/instance-metrics.e2e.ts
index 46577fe18..071b2531b 100644
--- a/test/e2e/instance-metrics.e2e.ts
+++ b/test/e2e/instance-metrics.e2e.ts
@@ -12,6 +12,14 @@ import { OXQL_GROUP_BY_ERROR } from '~/api'
 
 import { expectConsoleMessage, expectNoConsoleMessage, getPageAsUser } from './utils'
 
+// Freeze the clock so the default "Last hour" range and the calendar's visible
+// month don't depend on when the tests run. Without this, runs near midnight
+// UTC flake: the range straddles the day boundary, and on a month boundary the
+// calendar opens on the previous month, so the "Today" cell isn't rendered.
+test.beforeEach(async ({ page }) => {
+  await page.clock.setFixedTime(new Date('2026-06-15T12:00:00.000Z'))
+})
+
 test('Click through instance metrics', async ({ page }) => {
   await page.goto('/projects/mock-project/instances/db1/metrics/cpu')
 
@@ -76,31 +84,19 @@ test('Date range picker: invalid range shows an error', async ({ page }) => {
   const today = page.getByRole('button', { name: /Today/ })
   await today.click()
   await today.click()
+  await expect(page.getByText('Date range is invalid')).toBeHidden()
 
-  // Set the times explicitly rather than relying on the times inherited from
-  // the default "Last hour" range. When the test runs shortly after midnight,
-  // that range straddles midnight (start ~23:00 the previous day, end ~00:00
-  // today), so collapsing both dates to today leaves start after end and the
-  // range reads as invalid before we've done anything. Start with a valid
-  // same-day range (01:00 before 23:00): no error.
+  // set the start time (23:00) after the end time (01:00) on that same day
   const hours = page.getByRole('spinbutton', { name: 'hour,' })
   const minutes = page.getByRole('spinbutton', { name: 'minute,' })
   await hours.first().click()
-  await page.keyboard.type('01')
+  await page.keyboard.type('23')
   await minutes.first().click()
   await page.keyboard.type('00')
   await hours.nth(1).click()
-  await page.keyboard.type('23')
+  await page.keyboard.type('01')
   await minutes.nth(1).click()
   await page.keyboard.type('00')
-  await expect(page.getByText('Date range is invalid')).toBeHidden()
-
-  // now flip the start time (23:00) to be after the end time (01:00) on that
-  // same day
-  await hours.first().click()
-  await page.keyboard.type('23')
-  await hours.nth(1).click()
-  await page.keyboard.type('01')
 
   await expect(page.getByText('Date range is invalid')).toBeVisible()
 })