1) Can you tell me the location you set in OpenSprinkler options? The firmware uses the location to query the cloud server and get time zone (including DST). If you let me know the location, I can check.
2) Firmware 2.1.3 allows overlapping programs, and sequential stations will be guaranteed to be serialized. However, because this firmware does not use a station queue, each station is only allowed one schedule at a time. So if a station is requested to run when it’s already running (or already has an existing schedule), the new request will be ignored. This will affect repeating programs — for example, if you set a program to run station 1 for 1 hour, and repeat every 2 hours. Let’s say the watering percentage today is 250%, so the run time becomes 2.5 hours. The second time it’s requested to run (after 2 hours), the same station has’t finished the previous run, so the second request will be ignored. However, if by the second time it’s requested to run, station 1 has already finished the previous run, then it will be scheduled. Hope this makes sense.
If different programs run different stations, then you shouldn’t expect any problem. It’s only a potential issue if different programs run the same station (or one single program is set to repeat).