Hey  @arobert74,

Thanks for all the details. First off, you can find the hardware version of the Decos on the label of the node itself. Since you have two separate firmware versions, you likely also have two different hardware revisions. You can also always manually check if you are up to date by comparing the most recent firmware on your versions download page against the Deco app

The Xfinity Gateway - Was there an option to enable  Bridge Mode or IP Passthrough Mode?

For the connections:

Mesh Technology is specifically related to a feature that allows your network to move your phone between nodes. It will simply become your phone's responsibility to move between nodes. Before disabling this function, I would also try and disable both Beamforming and Fast Roaming as these are the features that deal with "moving" devices. (see this article for more info).

Lastly, if this is limited to phones, I would also make sure that you have private addresses disabled for your home network. Disabling this would allow your network to immediately know what device is connected, instead of seeing the phones as completely new devices.

  @arobert74,

If Bridge Mode is Disabled: 

Then the Operation mode of the Decos needs to be switch to Access Point or AP Mode from the Interface.

To use the Decos in their Default Mode (Router Mode) then you will need to ENABLE bridge mode and make sure your Decos are the only device connected to the ISP Gateway.

Right now, you have two DHCP servers assigning addresses, the one on the Decos and the one from the Gateway. With more than one, you will experience conflicts and longer waits for devices to build a valid connection. 

AP Mode on Deco will disable the Decos DHCP server (along with other features)

Bridge Mode on the Gateway will Disable the Gateway's DHCP (allowing full use of your Decos)

It is likely that once this is fixed, your last Deco will update to the latest firmware, otherwise you could follow the steps in this FAQ to manually upgrade: How to Upgrade Your Deco Firmware