Living parents. Best option for keeping old 4K Whole Home PVR

I think my parents have two 4K Whole Home PVR being used wirelessly and they’re very used to the UI. Unfortunately they’re paying way too much for crappy internet and two cell phones and tv. Now they have to move.

If they move into a residence that has bell fibe in the building can they keep their current receivers? Because if the answer is no, it would make more sense to install them as new customers to save money, even if that means new cell numbers.

Any way they can have a new account but use the old receivers? I hear bell is just not selling them anymore.

Any ideas? Or is there a way with the new bell streaming boxes to have a TV mode UI? The one they have is a more modern streamer box ui, but it’s a mess for older people who are used to a tv guide style ui.