Question
My vintage (1992) sprinkler controller is not following our instructions any more.  I even temporarily disconnected it from its power source hoping to get it to reset but that evening after I did that it decided to start with zone 6 at 8:30 pm.  We had it set to start zone 1 at 1:00 am

Any suggestions?

Answer
Well... I'd checking each program "A B & C" for a start time you don't know about. Make sure the AM & PM time is correct.
If you find no random start times, etc. You may need to replace the controller. Or, if the controller is consistently starting 5 1/2 hrs off, just change the current time of day by 5 1/2 hrs. I've saw more than one this way.

Good Luck, reply back if you need further help.

Matt