Cheers. Yes it is a Bosch mid drive. Never had error codes. I have already discussed converting it to a grip-shift - at my expense, which seems a bit rough as the test ride was on a UA with a grip-shift!
What concerns me is that Enviolo seem to think a new hub will fix the issue, guy at bike shop reckons it's not the hub but interface or servo.
Also when I gave Enviolo the hub serial number they said "This isn't a Cargo hub, but I expect it to be a Trekking". So there are different versions? And UA fit the wrong type?