End Time property in the Scheduler tab seems to be synchronizing with Start Time.
At first I had
Start Time : 2012-10-16T18:00:00 End Time : 2012-10-18T18:00:00
and edited as
Start Time : 2012-10-16T18:00:00 End Time : 2012-10-19T18:00:00
and once I saved it I saw this as a result
Start Time : 2012-10-16T18:00:00 End Time : 2012-10-16T18:00:00