diff --git a/packages/updatePrescriptionStatus/src/validation/content.ts b/packages/updatePrescriptionStatus/src/validation/content.ts
index 42a0c5a0b6..6e2ba719c1 100644
--- a/packages/updatePrescriptionStatus/src/validation/content.ts
+++ b/packages/updatePrescriptionStatus/src/validation/content.ts
@@ -13,7 +13,8 @@ export type ValidationOutcome = {
   issues: string | undefined;
 };
 
-export const ONE_DAY_IN_MS = 86400000
+export const ONE_HOUR_IN_MS = 60 * 60 * 1000
+export const ONE_DAY_IN_MS = 24 * ONE_HOUR_IN_MS
 export const LINE_ITEM_ID_CODESYSTEM =
   "https://fhir.nhs.uk/Id/prescription-order-item-number"
 export const NHS_NUMBER_CODESYSTEM = "https://fhir.nhs.uk/Id/nhs-number"
@@ -64,16 +65,24 @@ export function entryContent(entry: BundleEntry): Array<string> {
 
 export function lastModified(task: Task): string | undefined {
   const lastModified = new Date(task.lastModified!)
-  return isPastDate(lastModified, "lastModified")
+  const hasMetaLastUpdated = Boolean(task.meta?.lastUpdated)
+  // 24 hours if meta.lastUpdated is not provided, otherwise 999 hours
+  const allowedHours = hasMetaLastUpdated ? 999 : 24
+  return isWithinHours(lastModified, allowedHours, "lastModified")
 }
 
-function isPastDate(date: Date, fieldName: string): string | undefined {
+function isWithinHours(
+  date: Date,
+  hours: number,
+  fieldName: string
+): string | undefined {
   if (isNaN(date.getTime())) {
     return `Date format provided for ${fieldName} is invalid.`
   }
 
-  const today = new Date()
-  if (date.valueOf() - today.valueOf() > ONE_DAY_IN_MS) {
+  const now = new Date()
+  const limitMs = hours * ONE_HOUR_IN_MS
+  if (date.valueOf() - now.valueOf()> limitMs) {
     return `Invalid ${fieldName} value provided.`
   }
 }
@@ -84,7 +93,7 @@ export function metaLastUpdated(task: Task): string | undefined {
   }
 
   const parsed = new Date(task.meta.lastUpdated)
-  return isPastDate(parsed, "meta.lastUpdated")
+  return isWithinHours(parsed, 24, "meta.lastUpdated")
 }
 
 export function prescriptionID(task: Task): string | undefined {
diff --git a/packages/updatePrescriptionStatus/tests/validation/testRequestContentValidation.test.ts b/packages/updatePrescriptionStatus/tests/validation/testRequestContentValidation.test.ts
index 4cae1fa09f..813a04215a 100644
--- a/packages/updatePrescriptionStatus/tests/validation/testRequestContentValidation.test.ts
+++ b/packages/updatePrescriptionStatus/tests/validation/testRequestContentValidation.test.ts
@@ -35,6 +35,9 @@ import {
 } from "../utils/testUtils"
 
 describe("Unit test for overall task validation", () => {
+  beforeEach(() => {
+    jest.useFakeTimers().setSystemTime(DEFAULT_DATE)
+  })
   it("When task is valid, should return true with no issues.", async () => {
     const expectedOutcome = {valid: true, issues: undefined}
     const entry: BundleEntry = {fullUrl: FULL_URL_0, resource: validTask()}
@@ -141,9 +144,6 @@ describe("Unit tests for pre-cast validation of bundle", () => {
 })
 
 describe("Unit tests for validation of lastModified", () => {
-  beforeEach(() => {
-    jest.useFakeTimers().setSystemTime(DEFAULT_DATE)
-  })
 
   it("When lastModified is over a day in the future, should return expected issue.", async () => {
     const futureDate = new Date(
@@ -175,12 +175,33 @@ describe("Unit tests for validation of lastModified", () => {
 
     expect(actual).toEqual(undefined)
   })
+
+  it("When meta.lastUpdated present, lastModified <= 999 hours into future should be valid.", async () => {
+    const withinWindow = new Date(
+      DEFAULT_DATE.valueOf() - (998 * 60 * 60 * 1000)
+    )
+    const task = {lastModified: withinWindow.toISOString(), meta: {lastUpdated: DEFAULT_DATE.toISOString()}}
+
+    const actual = lastModified(task as Task)
+
+    expect(actual).toEqual(undefined)
+  })
+
+  it("When meta.lastUpdated present, lastModified > 999 hours into future should return expected issue.", async () => {
+    const futureDate = new Date(
+      DEFAULT_DATE.valueOf() + (999 * 60 * 60 * 1000 + 1000)
+    )
+    const task = {lastModified: futureDate.toISOString(), meta: {lastUpdated: DEFAULT_DATE.toISOString()}}
+
+    const expected = "Invalid lastModified value provided."
+
+    const actual = lastModified(task as Task)
+
+    expect(actual).toEqual(expected)
+  })
 })
 
 describe("Unit tests for validation of metaLastUpdated", () => {
-  beforeEach(() => {
-    jest.useFakeTimers().setSystemTime(DEFAULT_DATE)
-  })
 
   it("When meta.lastUpdated is over a day in the future, should return expected issue.", async () => {
     const futureDate = new Date(