@foo4,

Have you tried to got through a full reset process for the devices? 

Since you have a new network, you will need to go through the setup process in the app - and you may need to either reboot or reset the switches if they have been offline for awhile.

At what specific point in the setup process do you see the device's timeout? What is the status of their LED indicators?

If you are relying on using the same credentials for your new router, there is always a chance that the connection wont work (As there was a lot more changed besides the SSID and password at a technical and security level)

  @foo4,

I think you are correct. That exact action sounds like the device is attempting to connect with the correct credentials but never receives the go-ahead to actually connect. 

2.4 Compatability could be a factor in this case, such as if this switch is closer to the router than your other switches and is having 5GHz pushed on it.

I would also recommend checking your Network Security settings. While the devices should support most common home Wi-Fis, it has always been the case where some older IoT devices will have difficulty connecting to networks with the latest protocols. If you have an IoT network or guest network, try adding the device to that network (Even if it still has 5GHz, it wont have as strong of supporting features to 'guide' the device to other bands).

It could be possible that the 'fix' is already available for this behaivor, it may just be a firmware update though - Is there any network that you could use to perform the intial setup and see if there is a firmware update?

Otherwise, you are probably best suited to go thorugh our support teams directly - as they may have direct compatability information or steps they can take to help get the device configured.