Ok folks, car went in to Dealers today...third attempt at fixing the "yellow i"....
After doing lots of tests, they declared the Dashcam was causing the fault. I pointed out the Dashcam had been running for months with no problem, PRIOR to the last software update, which is when the problems occurred. Also the error says "low 12volt battery", which it clearly is not...car sits at 14.4volts when running, and never below 13 volts when off.
Ora themselves told the Dealer "oh, its harmless" !!! No answer, no fix. In reality, the "low 12volt" warning disables climate control, drops heating to non-existent, disables rear demister, disables interior lights....etc etc
I reluctantly took the car back. As a test, I disconnected just the Rear facing dashcam, leaving main cam working...that has fixed the issue.
I can only think the recent Update has made the electrical sensors much more sensitive to extra current draw, a bit like in a fuel car with a Canbus system.
Hope this helps anyone having this "harmless" issue.