I have been looking into the IMC rating as part of the idea to introduce an EASA rating that permits some IFR flying without having an IR.
The IMC Rating in so far as it permits IMC flight under IFR is only valid in UK airspace.
When the law refers to UK airspace it refers to the UK Teritorial Airspace which is that airspace above the teritorial limits of the UK. This is not to be confused with FIRs which are separate boundaries set up for the purposes of coordination of traffic.
Since the Government of the CI permit the use of the IMC rating in their teritory then the fact that it lies within the French FIR makes no difference day or night. The French can not legislate away the privileges of the CI Government to regulate within it's own soverign territory.
Therefore one can exercise the IMC privileges of the IMC rating departing the UK until 12nm from the coast and when in the CI once within their teritorial airspace - 12nm for Jersey and 3nm from States of Gurnsey (median line with French teritorial airspace if applicable.
It is the bit in the middle that is the problem for both the IMC holder wishing to fly in IMC and the NPPL SSEA holder wishing to take advantage of the new ability to fly in the CI airspace. In International Airspace (outside the territory of all countries), ICAO provisions apply.
If the FIR boundary was the limit then there would be IMC rating holders who could not fly in parts of the UK while at the same time IMC holders could fly in airspace that is outside the UK!!!!!! The law refers to teritorial limits because the UK can not legislate for what is permitted in another country's teritorial airspace.
Brendan.