[RELEASE] 5-2 Day Programmable Thermostat Scheduler (Weekday, Weekend) with Remote Temperature Sensor for each Schedule

Most definitely if one timer is missed/times out (which I’ve seen happen some time ago and I thought ST had fixed it) then the entire chain stops, so when you change settings it bootstraps it. So adding another timer to bootstrap won’t help, the root of the issue needs to be found as to why a timer would not fire.
And no it doesn’t matter if the thermostat doesn’t respond or is even offline the app runs independent of the device.
Maybe start a separate thread on why timers won’t fire and some users can throw in their thoughts. here’s one thread where I had reported that timers don’t fire.