Orbi MESH is only intended to support indoor home use and some just out side of the home. Not intended for whole property coverage.
Actually v.21 was the most stable version of FW. Was fully beta tested and had great results and opertion.
Was first FW version to support a separate IoT network...
If your distances between the RBS and RBS and each other is good, say 30 feet, the RBS will connect to each other if placed out in a line from each other. Called daisy chain on the 50 model. If you want or need the RBS to connect to each other, then daisy chain needs to be enabled on the RBR.