well it is actually, but fairly simple
have had to run on 95 Ron for the last 3 weeks due to no supplies locally of the 98+ stuff, just been topping up £15-£20 a time - but actually ended up doing about 300miles on it - anyway, normal service was resumed last night and was able to fill from "fumes" level to full (£97.00 worth )
so the question - the ecu has likely wound the timing back to protect (as I understand it ) - how many miles (roughly) do I need to do before I can get back to normal "spirited"