The S1300 was updated to v3:203, which caused it to become inaccessible in MESH mode. It was then reverted to v3:105, where it remains and when MESH mode is entered, the unit is not accessible by wired or wireless connection. I have performed a reset, have reflashed with v3:105, and the unit remains inaccessible as soon as I press the mesh button and it enters mesh mode. It appears that the unit is not providing DHCP support in mesh to any connected client, and even with a client on a static IP, it remains inaccessible.
The B1300 has not been updated.