I had an invalid time for the default time with a timerange parameter, and the bug was quite poorly indicated, killing a bunch of time.
tr= getParam( 'timerange', '021-06-08T07:22:49.300Z/2021-06-08T07:22:49.800Z', 'timerange to load' )
Also, this morning when using min and max constraints, it seemed like Autoplot should trim the requested time to the min and max.
This error message was with the AutoplotDataServer, so maybe it's just in there that the feedback is poor.
It was really more a problem with JythonDataSource. I've improved feedback when the default timerange is not parseable.