The error says it all: Start time must be prior to end time.
If you are trying to run a program over midnight, you can set the program end time to be 23:59. Once the program starts (say, at 23:00) it will continue running until all the scheduled stations have completed, even if it runs over the end time (23:59).
OK – I understand.
Still it makes more sense to me if the scheduled time would take the 24 hours in concideration … I mean start time 23:00 is prior to 06:00 when it comes to understand how a clock works