I can see that this has been requested in the past but then the posts seem to die a death with no sign of the feature being implemented in the app so...again...why can't we set an alarm to play on a specific group of speakers rather than only having the option to "include grouped rooms"?
Use case: I have speakers in a bedroom, kitchen and living room. In the evening I often want to listen to music in the kitchen or bedroom while someone is watching TV in the living room so I ungroup my speakers. In the morning I want my alarm to play a radio station or play list on all speakers throughout the house. As it stands, unless I remember to re-group my speakers before going to sleep for the night the alarm will only play in the bedroom. Why can't I have a set of ticket boxes to select exactly what speakers to play the alarm on?
The only possible reason to not have this feature that I can think of is that it could cause confusion or frustration if an alarm interrupts a speaker that is already playing. For that case, why not have an additional Yes/No box to indicate whether I want my alarm to override a speaker if it's already playing or to ignore the active speaker and only sound on those that don't already have something playing?
Thankfully I have found a workaround to implement this feature myself by using a third party home automation hub but all this does is suggest that the feature can definitely be easily implemented as it's been achieved via reverse engineering and for Sonos not include it in their own app is just either poor design or laziness.