Firstly you've posted in the V6 board but asked about a TiVo.. which box do you have? Check here if you're not sure
It probably won't alter the outcome too much, to be fair - you can access UK-TV OnDemand content via the Home > CatchUp & Home > OnDemand menus.
VM don't have the UK-TV app on their TV boxes, and to be fair it's probably quite low down the priority list compared with some others.
Virgin TV boxes don't have an app-store in the way that Android & iOS does - apps have to have commercial agreements with VM, and be written for the TiVo/360 platforms, and Virgin install them automatically.
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