I have told the garage I would prefer to return the vehicle as have no confidence in it - funnily enough doing 70-0mph in 2 seconds was not my idea of fun. They seem to be glossing over that particular issue.
I was advised by them that I can't return the car until they have had the opportunity to fix the issue, but they seem to think it's just simply an ignition barrel...
They haven't mentioned if the (voicemail message) if the issue picked up by the AA Diagnostic has been resolved, nor the issue re loss of power.
The ignition fault was intermittent and all lights on the dash came on when key turned, and auto start stop light when amber to green.
So frustrating, but I appreciate your help.
Suicidal/Russian roulette run commute here I come :)