Just a thought, when you erased your iPhone did you then "restore from backup"? If so, this will of copied back any problematic settings. However, if you setup as a new iPhone and tested wifi before installing anything else, it would rule out corrupt settings.
Good point! Thanks for that.
When I have time, I’ll erase again and try with a “raw” phone. If that works, the challenge then is to get all the stuff I have back into the phone without the settings that might be the cause of the problem!
Maybe if I erase all network settings, then backup, before trying the above, I can restore from a copy devoid of network stuff which, hopefully, would then leave the phone working on the Wholehome!!
A posting elsewhere triggered me to examine what was different between my iPhone and iPad- VPN was the answer. I have TunnelBear on both, but it only autoconnects on the iPhone (because my iPad is 99% used on my own, trusted, networks).
Turning off auto connect fixed the problem and I have now marked the network as trusted and turned auto connect back on.
This begs the question of why I was not getting some better alert than the WiFi symbol disappearing to tell me the connection was not completing properly (timing issue?) but that is a minor point. Just delighted to have Wholehome working for all devices so I can turn off previous network.
Now getting a steady 180Mbps WiFi speed or close to it all over the house.