Thanks for posting on the community.
Yes when you search the On Demand content you will find many programs that were aired a long time ago but these won't be available to watch.
Unless they're box sets or movies then programs are only usually available up to seven days so I would recommend setting up a bookmark for this program so it will record if it's aired again.
I hope this helps, please let me know if there's anything else I can help with.
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