fix: backdate initial guide generation at startup

server/src/services/TvGuideService.ts

@@ -189,7 +189,11 @@ export class TVGuideService {
     );
   }
 
-  async buildAllChannels(guideDuration: Duration, force: boolean = false) {
+  async buildAllChannels(
+    guideDuration: Duration,
+    force: boolean = false,
+    startTime: number = +dayjs(),
+  ) {
     return this.withGuideContext(async () => {
       if (isEmpty(this.channelsById)) {
         const placeholderChannel = await this.makePlaceholderChannel();
@@ -198,7 +202,13 @@ export class TVGuideService {
         delete this.cachedGuide[PlaceholderChannelId];
         await Promise.all(
           keys(this.channelsById).map((channelId) =>
-            this.buildChannelGuide(guideDuration, channelId, false, force),
+            this.buildChannelGuide(
+              guideDuration,
+              channelId,
+              false,
+              force,
+              startTime,
+            ),
           ),
         );
       }

server/src/tasks/UpdateXmlTvTask.ts

@@ -84,9 +84,22 @@ export class UpdateXmlTvTask extends Task2<typeof UpdateXmlTvTaskRequest> {
           true,
         );
       } else {
+        // Round start time down to the nearest hour so guide boundaries align
+        // with the hour-granular requests made by the UI and other consumers.
+        // Extend the duration by the fractional hour we went back so the guide
+        // end time — and therefore coverage before the next scheduled run — is
+        // identical to what it would have been without rounding.
+        const now = dayjs();
+        const startTime = now.startOf('hour');
+        const extraDuration = dayjs.duration(now.diff(startTime));
+        const guideDuration = dayjs
+          .duration({ hours: xmltvSettings.programmingHours })
+          .add(extraDuration);
+
         await this.guideService.buildAllChannels(
-          dayjs.duration({ hours: xmltvSettings.programmingHours }),
+          guideDuration,
           false,
+          startTime.valueOf(),
         );
       }