3 zone help

I reached out to tado support about this, but weren't very helpful for this particular problem, so wondering if someone here can help me.

My house has 3 zones: Zone 1 - room radiators upstairs with 1 thermostat, Zone 2 - bathroom radiators controlled by a digital timer and TRV's, and Zone 3 - underfloor heating downstairs with 3 thermostats. All zones are activated/deactivated by a zone valve in boiler cupboard.

I'm looking at replacing zone 1 + zone 3 with a tado wired thermostats, that's fine and should just be a case of switching thermostats.

But what I'd also like to do is control zone 2, the bathroom radiators with tado also. Currently this is controlled by a digital timer in the boiler cupboard with TRV's on the bathroom radiators. I want to know if either of these two options are possible:

  1. Just put tado TRV's on the bathroom radiators and have the timer 'always on'. Can TRV's work independently? i.e. I don't want them to call heat from zone 1 or 3
  2. If that's not possible, could I replace the current digital timer with a tado extension kit? The digital timer for the bathroom radiators is also right next to the digital timer for the hot water. Could I plug them both into the extension kit? I understand this would probably be a job for a pro.