25 is just obscene. Should configurable somewhere so you can simply press it on rare occurrences it is required.
For me it would be simply set all TRVs to 21 if we have elderly visitors rather than having to manually select each room individually which you still have to do with existing button rendering it useless.
Only use case for it at present is if the boiler is being serviced during summer.
Or you could just use (for example) an Alexa voice routine ......." Alexa.....Boost Heating" and it will "Boost" your preferred tado° rooms to your required "Boost" temperature for as long as you have set in your tado° "manual activation" feature of your tado° room.........it really is that simple......no opening of the App......no clicking on any settings.....just using your voice.
However.....you do need to have Alexa.......luckily I do.