Nest / WiFi Adventure

I've been merging my IoT and AV class C networks into 1 class B network so the automation can talk to the home entertainment devices easier and bring back order to my IP addresses for better filter of what has access to what. For the most part it has just been tedious updating the info close to 200 devices. While I was reconfiguring the house WiFi APs (Access Points) , I set them to enable roaming (AP swap you off to closest AP automatically) which in the case of Unifi APs assumes WAP2 encryption. Most devices handled this just fine but others had a real problem with it. For instance my wired (AC powered) Nest Protect continued to work fine but the battery powered one and the thermostat, in the house, both switched to the shop network I had not changed yet. So technically they were connected but not with enough signal to actually work. Some devices just reconnected no problem while others required a reboot, reconfig or, as in the case of the Nests, flat out refused to connect. So I've had to forget the roaming / zero hand off setup and use a configuration that support multiple encryption methods.