Mist - Wired Assurance - Networks propagated across Campus Fabrics

Not sure if anyone has the same setup but we have multiple EVPN Multihoming Campus Fabric configured under the same Site. Recently we learned, rather the hard way, that if the Fabrics are in the same Site, Mist will automatically propagate a (Layer 3) Network that you configure in one Fabric, to the other Fabric. This means the switch pair in the other Fabric will actually share the same IP addresses which created major issue for our setup.

The advice from Juniper is to only have one Campus Fabric per site so now we have to tear down one of the Fabrics and redeploy it in different Site.