Is there a bug in the latest firmware causing unexpected reboots? It's happened to me and I've seen other posts in the forums with similar issues. Last night my device ran zones 1 and 2 of my 5-zone program, then rebooted soon after starting zone 3.

I'm sending diagnostics now. This is what I see in the log from last night:

2018-06-22 03:30:01,849 - INFO  - rmPrograms:743 - Automatic Cycles [{'zoneLinesData': [userPercentage:1, coef:1.0, flag:0, calc_wd:0, active:True, zid:1, duration:330, order:1, userPercentage:1, coef:1.0, flag:0, calc_wd:0, active:True, zid:2, duration:330, order:2, userPercentage:1, coef:1.0, flag:0, calc_wd:0, active:True, zid:3, duration:330, order:3, userPercentage:1, coef:1.0, flag:0, calc_wd:0, active:True, zid:4, duration:330, order:4, userPercentage:1, coef:1.0, flag:0, calc_wd:0, active:True, zid:5, duration:1230, order:5], 'cycle': 0}]
2018-06-22 03:30:01,857 - INFO  - rmProgramScheduler:181 - Zone 1 is SIMULATED (db_rowid=1401, zid=1, day=1529640000/2018-06-22 00:00:00, forecastID=2533, forecastTime=None/None, coef=0.51, aw=0.00, wp=50.87, userWateringTime=649.00, computedWateringTime=330.00, condition=0)
2018-06-22 03:30:01,859 - INFO  - rmProgramScheduler:184 - Zone 1003 is not simulated won't carry available water
2018-06-22 03:30:01,862 - INFO  - rmProgramScheduler:181 - Zone 2 is SIMULATED (db_rowid=1402, zid=2, day=1529640000/2018-06-22 00:00:00, forecastID=2533, forecastTime=None/None, coef=0.51, aw=0.00, wp=50.87, userWateringTime=649.00, computedWateringTime=330.00, condition=0)
2018-06-22 03:30:01,864 - INFO  - rmProgramScheduler:184 - Zone 1003 is not simulated won't carry available water
2018-06-22 03:30:01,867 - INFO  - rmProgramScheduler:181 - Zone 3 is SIMULATED (db_rowid=1403, zid=3, day=1529640000/2018-06-22 00:00:00, forecastID=2533, forecastTime=None/None, coef=0.51, aw=0.00, wp=50.87, userWateringTime=649.00, computedWateringTime=330.00, condition=0)
2018-06-22 03:30:01,870 - INFO  - rmProgramScheduler:184 - Zone 1003 is not simulated won't carry available water
2018-06-22 03:30:01,872 - INFO  - rmProgramScheduler:181 - Zone 4 is SIMULATED (db_rowid=1404, zid=4, day=1529640000/2018-06-22 00:00:00, forecastID=2533, forecastTime=None/None, coef=0.51, aw=0.00, wp=50.87, userWateringTime=649.00, computedWateringTime=330.00, condition=0)
2018-06-22 03:30:01,875 - INFO  - rmProgramScheduler:184 - Zone 1003 is not simulated won't carry available water
2018-06-22 03:30:01,877 - INFO  - rmProgramScheduler:181 - Zone 5 is SIMULATED (db_rowid=1405, zid=5, day=1529640000/2018-06-22 00:00:00, forecastID=2533, forecastTime=None/None, coef=0.62, aw=0.00, wp=61.89, userWateringTime=1987.00, computedWateringTime=1230.00, condition=0)
2018-06-22 03:30:01,918 - INFO  - rmProgramScheduler:242 - Program 1 added to watering queue and/or watering history
2018-06-22 03:30:01,922 - INFO  - rmProgramSchedulerWatering:232 - Watering - starting zone: (uid=None, pid=1, zid=1, ust='2018-06-22 03:30:00', rst='2018-06-22 03:30:01', ud=649, md=330, rd=0, aw=0, flag=0, manual=False, running=True)
2018-06-22 03:35:31,501 - INFO  - rmProgramSchedulerWatering:272 - UpdateZone available water: 0
2018-06-22 03:35:31,539 - INFO  - rmProgramSchedulerWatering:140 - Watering - zone finished: (uid=None, pid=1, zid=1, ust='2018-06-22 03:30:00', rst='2018-06-22 03:30:01', ud=649, md=330, rd=330, aw=0, flag=0, manual=False, running=False)
2018-06-22 03:35:31,544 - INFO  - rmProgramSchedulerWatering:232 - Watering - starting zone: (uid=None, pid=1, zid=1003, ust='2018-06-22 03:30:01', rst='2018-06-22 03:35:31', ud=30, md=30, rd=0, aw=0, flag=0, manual=False, running=True)
2018-06-22 03:36:01,596 - INFO  - rmProgramSchedulerWatering:140 - Watering - zone finished: (uid=None, pid=1, zid=1003, ust='2018-06-22 03:30:01', rst='2018-06-22 03:35:31', ud=30, md=30, rd=30, aw=0, flag=0, manual=False, running=False)
2018-06-22 03:36:01,599 - INFO  - rmProgramSchedulerWatering:232 - Watering - starting zone: (uid=None, pid=1, zid=2, ust='2018-06-22 03:30:02', rst='2018-06-22 03:36:01', ud=649, md=330, rd=0, aw=0, flag=0, manual=False, running=True)
2018-06-22 03:41:31,248 - INFO  - rmProgramSchedulerWatering:272 - UpdateZone available water: 0
2018-06-22 03:41:31,285 - INFO  - rmProgramSchedulerWatering:140 - Watering - zone finished: (uid=None, pid=1, zid=2, ust='2018-06-22 03:30:02', rst='2018-06-22 03:36:01', ud=649, md=330, rd=330, aw=0, flag=0, manual=False, running=False)
2018-06-22 03:41:31,290 - INFO  - rmProgramSchedulerWatering:232 - Watering - starting zone: (uid=None, pid=1, zid=1003, ust='2018-06-22 03:30:03', rst='2018-06-22 03:41:31', ud=30, md=30, rd=0, aw=0, flag=0, manual=False, running=True)
2018-06-22 03:42:01,341 - INFO  - rmProgramSchedulerWatering:140 - Watering - zone finished: (uid=None, pid=1, zid=1003, ust='2018-06-22 03:30:03', rst='2018-06-22 03:41:31', ud=30, md=30, rd=30, aw=0, flag=0, manual=False, running=False)
2018-06-22 03:42:01,344 - INFO  - rmProgramSchedulerWatering:232 - Watering - starting zone: (uid=None, pid=1, zid=3, ust='2018-06-22 03:30:04', rst='2018-06-22 03:42:01', ud=649, md=330, rd=0, aw=0, flag=0, manual=False, running=True)
2018-06-22 03:45:46,321 - INFO  - main:50 - RainMachine v2 Copyright (c) 2015 Green Electronics LLC
2018-06-22 03:45:46,331 - INFO  - main:51 - Running on platform Android
2018-06-22 03:45:46,334 - INFO  - main:66 - Waiting for IP address (0/40) Current: None

Note that at 2018-06-22 03:42:01,344 it said it was starting zone 3 but the next entry is the device restarting. I'm not sure if it did actually run that zone for a little while or if the reboot was immediate.