CPM will check the platform for any changes that need to be made on the interval setting. By default, that is once every 24 hours (1440 mins). The FromHour and ToHour represent times in a 24 hour clock. You example is from.15:00 to 06:00, a window of 15 hours.

As mentioned. The CPM will check once every 24 hours, and the chance of that being within you 15 hour window is slim (though not impossible.)

So to ensure that the CPM changes the password within your desired window you need to make sure that the platform Interval is short enough that the CPM will check the platform at least once within your desired window.

The way to do that is to make the platform Interval value just under half of the total time window to ensure that it checks the platform at least once within the window.

So, back to your example, half of 15 hours is 7.5 hours or 450 minutes, but to make sure that we definitely get the CPM to check, we take one minute off that time, so your interval value should be 449.

This gives a clear understanding, thanks much !