I think you raise a good point Graham, to me any expat living within the EU wanting to see an exit from the EU is about as barmy as turkey voting for Xmas.
I'm sure that the Spanish would make us just as welcome as they did before we joined the EU and will be just as happy to relieve us of our hard earned.
I know quite a few folk in GA, expats, with serious long term health conditions that are being treated to a very high standard by the Spanish Health Service who would be completely snookered if they had to try and obtain a health insurance policy, if indeed they could find a policy the cost would be prohibative.
I'm pleased to say that its not a problem we will have to face as our visits to GA are only for a month at a time, albeit three or four times a year............if I was a resident with only a few years of residency I would be worried.
In saying that none of us know what will happen or the extent of any exit that could possibly happen.
Regards all
John