Sorry - I should have warned you. This seems to be a bug in the I.S. - I had the same experience. Once the picture row size is 1" or greater, it will not allow you to set it to less than 1". Maybe you can duplicate and edit the duplicate scheme; otherwise you may have to re-create the schedule.
Karl
One of the forum moderators
AC 28 USA and earlier • macOS Sequoia 15.2, MacBook Pro M2 Max 12CPU/30GPU cores, 32GB