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Catch Up and On Demand content is made available to us by the broadcasters themselves. As such, any limitations regarding availability are due to the licensing agreement we have with these broadcasters.
If a programme or episode is no longer available, this would suggest that we are no longer permitted to supply this content. If it is only available as a chargeable film or box set on the Virgin Media Store, this is a streaming service available to customers and non-customers alike, which allows you to buy and keep a wide variety of content.