mapleworth, you have a French ICAO licence which will be valid for flight within the UK whatever happens. I presume your aeroplane has a full C of A (you do not say) and therefore will be able to be transfer to the French register when you move to France whatever happens, should you wish.
It is too early to say what the outcomes will be but there is no need to be too concerned. Subject to ICAO your compliant UK aircraft will be valid for flight throughout the world including easaland - whether it has an EASA stamp or not. Should EASA throw UK Flight Examiners and engineers overboard on the 31 st December is unlikely, we are yet to discover. Once the UK is out of EASA and there is no agreement stipulating otherwise then there will be nothing to stop you retaining you French licence and based on it obtaining a UK PPL in addition.
Last edited by Fl1ingfrog; 13th Oct 2020 at 19:45.