We are looking for exactly this functionality also.
We have custom thresholds set for a lot of volumes , IOPS wise, but every morning we come in to Inbox's full of alerts triggered by the overnight backup runs.
If we could have multiple scheules to define different thresholds by time of day/week it would be perfect 🙂
If not if we could at least disable them during a time window it would be better than what we come in to every morning now.
My fear is with so many 'false' alarms real events will get missed as we keep winding the thrsholds up to try and reduce the spam.