What does a restart day of 0 in a schedule do?

What does a restart day of 0 in a schedule do?

When you set the restart day to 0, it means that the schedule will run through all the segments (days) and then it will stay on the final day and not restart.

If you want to program a schedule for a single day and have it repeat forever both a restart day of 0 and 1 will work.