3MTA3,
Many thanks for that and welcome to Virgin!
The problem has arisen because apparently the UK authorities have informed the French of how little UK tax we pay (approx 2%) which is well below the 2/3 you suggest. The 180 day rule shouldn't be a problem but they still want their cut. Whilst I have no aversion to paying SOME tax in France, when I spend so much time abroad I'd rather not be liable for the full monty.
I don't use a tax adviser in the UK and do the annual return myself. I have used Wilfred T Fry (Hastings) in the past but left them due to their high charges.