That highlights a difference between scheduled climate and scheduled charging. Scheduled charging is a function built into the car, and you can set a charge schedule using the car menu. If you use the app to schedule charging, you can get into the car and look in the settings and see the schedule that you set with the app. When the app went out a few days ago the charge schedule that I had previously set with the app still ran.
Climate on the other hand cannot be scheduled in the car, only in the app, which makes me suspect that the app sends the climate command to the car at the appointed time, basically the same command as if you pressed "Turn on Climate". If there is no connection at that time then climate will not start. Once started even if connection is lost the car will automatically turn off climate after thirty minutes.