Excellent question @AZqueen! This can be done with the addition of an open window magnet for the contact sensor. This way you will have two magnets, one for the closed position and one for the desired open position.
There is also the option to bypass a sensor, basically instructing the Alarm to ignore a particular sensor during the time frame that it is armed in a mode. Check out our help center article about bypassing devices, for more information. I hope this helps!
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