In the main Worcester boilers use Wave not Hive, so it would depend how the Hive was installed. Hive is a simple off/on switch it is not analogue like Wave, and it could connect direct to boiler, or it could connect to a motorised valve which in turn connects to boiler.
There are two versions of Hive one has to be 230 vac the other has volt free contacts. However you can over ride Hive turning heating on standard method for frost protection and of course switch off Hive, however can't see how you could wire a two way switch as such as Hive would not know what's going on.
I don't really like Worcester or Hive, Worcester will not allow you to use third party analogue thermostats like Nest and Hive is a simple off/on switch with no link to TRV's.
However I would not rip either out once fitted. I have wifi TRV heads but not the best, they should link to Nest but since Worcester does not support opentherm never bothered to fit it.
I can see the advantage of switching the heating off/on with phone, but not up/down of a wall thermostat, as room temperature controlled by TRV all the wall thermostat does is turn off whole of heating on a warm day. Only with an open plan house with a wall thermostat control whole house.
However it seems many Worcester Bosch boiler require you to open the gas sealed bits to gain access to wiring, so not sure how you would change what does what without going into gas sealed bits?
As the Hive you can over ride the on or over ride the off, however I would assume you want it to be temporary? I have two thermostats wired in parallel and one is programmable so if cold I over ride the programmable thermostat knowing at next timed change it will revert to program, I assume you want same?
So it may be easier to add a cheap programmable thermostat in parallel to Hive than try and access the wiring for timer.