I agree, of course, with the basic meaning of the word as suggested by Parrot and commenters; however, I fail to see quite how this works in the given TV context.

My guess would be that they are referring to a form of 'off-line' storage with less easy access (for example) than everyday 'on-line' use), but not going so far as permanent archiving (clearly not appropriate here).

But I'm blessed if I know how to express that succinctly in English — I know many companies for example have 'redundant plant stores', but I don't know if you could really say 'a redundant film stroage system'!

Good luck, mate!