From a very quick check, these look like old episodes and so wouldn't fall under the "CatchUp" category.
Sometimes the "OnDemand" library does have complete past series such as these, but they'd fall under the BoxSet banner. I can't check my V6 at the moment, but if they're available on the My5 website, there would be a very strong chance they're available via the C5-branded app.
That app is indeed only on V6 & 360 boxes. TiVo users can only access the standard VoD library.
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