Hi.
Managed to update it to a newer version.
A friend has an up to date Connect Home, We added my device as a Sub (mesh wifi) then the Main Connect Home prompted to update. It was updating the Sub device.
It did this several times until the FW version in the sub device was the same of the main device.
After doing that we removed it from being a sub device and could add it to my account.
So, confirmed that being in a outdated firmware version will cause error 36-302.