Identify an automatic file change
Note which episode appeared or disappeared and whether it had been watched to completion. Apple’s current guide says the mobile feature automatically downloads the next two episodes of shows started in Continue Watching and deletes them after viewing. That behaviour can explain a changing offline queue.
Compare the local Downloaded area with the series or Library listing. An episode absent from device storage is not necessarily absent from the account’s available viewing offer. Conversely, a series tile remaining visible does not establish that a completed offline file is still present on the phone.
Inspect the iPhone or iPad preference
The documented route is the device Settings app, Apps, TV and Automatic Downloads. Read the present setting on the actual device used for travel. Do not assume the same behaviour from a television or from the Mac setting, which Apple describes separately.
Decide whether an automatically changing queue suits the intended session. Someone watching steadily through a series may prefer it, while someone preparing several specific episodes for a trip should check the resulting list carefully. A preference that worked for home viewing may not produce the exact offline itinerary desired.
Verify the departure queue explicitly
Apple says automatic downloading requires Wi-Fi. Before leaving connectivity, compare the completed downloads with the intended episode list and check the available viewing conditions. An episode appearing in Continue Watching is a navigation cue, not proof that its file finished downloading.
If unexpected cleanup continues, report the device, operating-system version, Automatic Downloads state and the episode’s viewing status. Keep the question about local automation separate from a missing purchase or expired channel entitlement. Do not buy another season merely to replace an episode removed from local storage after it was watched.
Questions about this guide
Can this setting remove finished episodes automatically?
Apple’s current mobile guide says watched automatic downloads are deleted.
Does the same guide describe identical Mac behaviour?
No. Apple describes the Mac automatic-download preference separately.