networking – What triggers asking connected device to reconnect to WiFi router?

I am assuming that changing the SSID and security would require the connected device to re-connect to the WiFi network. So, if that is true, in theory I can set anything in my WiFi router if it still retain the same SSID and security, is this about right?

Context

My house has 6 IP CCTVs, some of which are hard to reach, so I really avoid having to reconnect to the WiFi network. The way my network set up is I have a main router A and router B, which connected to router A through ethernet cable. With the current setting, router A and B has different SSID, so I would need to manually change the network should I am closer to the other, which is not ideal. Therefore, I would like to follow this guide.

My CCTVs are connected to router B, so instead of copying the setting from main router, like in the guide, I would do the other way around — matching the main router’s SSID and security to router B. Aside from that, the others should be the same.

Again, my question is this — in the above method, although changing how the router behave, I did not change the SSID and security of router B, so is it correct to assume that it won’t require the devices to reconnect to it?

Any help would be greatly appreciated!