Ok, further to that.
Today I have made a complaint to the Plumbers, Gasfitters and Drainlayers Board as follows.
"I would like to complain about the current situation regarding LPG on Boats.
To get a gas cert for the vessel is currently impossible without a complete reinstall.
The issue is that despite current standard, page iii "This Standard includes a statement that its requirements do not apply retrospectively" the gas fitters are insisting on compliance with the CURRENT standards, even for an EXISTING installation. This is in direct contradiction to the current standard,