Given the quite scathing summary Andrew Haines described in the paper - it basically says there is little benefit in not remaining a full EASA member and a whole load of serious issues if not - I can sort of understand for certain sectors, there will be big problems.
My CAMO has already stated that if they have to go through a reregistration process, they will be retiring. They've had more than enough problems and cost over recent years dealing with EASA changes. They won't be doing that again.
But the CAA has been VERY quiet over recent months so we don't know where they are at with preparations. Still now we have Grant Shapps/Michael Green as SoS for Transport, all will be well ....!