Converting from zone control to Radiator control.

[Frosty2062]

Hi Everyone.
I have a 2 zone system that has been running ok for the last 3 years.
I have a the controller in the Ground floor hall with a bypass rad and all others on TRV’s.
I have a stat on the first floor again in a room with a bypass rad and all others on TRV.
Both stats are bound to their own zone relay.
The system is a non vented system with 2 zone valves.
Everything works fine and as it should.
What I’d like to do now is convert 1 zone to programmable rad valves while leaving the other working as it is now.
First off is this possible?
If I do, I assume the rad valves are programmed to the zone relay but do I have to fit one to the bypass rad otherwise won’t it be on all the time?