Upgraded to 12.0 and has a problem with AG backup alarm (4339750)

Problem with the backup alarm now:on  AlwaysOn cluster. The AGs are all primary on node 2 right now, it it keeps saying the backups on node 1 haven't been taken in a long time. Shouldn't this be automatically ignored because these databases are in an AG?

Check what is the preferred node for backup?

This can be checked from SSMS->Always on Availability Group Menu and-> select required availability group and go to "properties":

Make sure it is not set to secondary preferred.  You should set it to primary preferred and the alarm should clear then.