These are just some of the inequalities in terms of citizenship rights that exist between the UK and Spain, let alone the other member states.
"Spaniards in Britain have the option to apply for UK citizenship after five years of residence, and joint nationality is available, but the situation for Brits in Spain may be very different.
Firstly, Spain only offers joint nationality to citizens of its former colonies, who can apply for dual or full citizenship after two years of residence, whilst everyone else has to prove 10 years of continuously living in the country.
Additionally, many Europeans in Spain – particularly pensioners and those living in 'expat belts' – speak little or no Spanish, which would preclude them from applying.
In practice, citizenship requirements are not very demanding – a multiple-choice quiz on aspects of legal, cultural, geographical and political life, and a test to prove Spanish language ability of level A2, equivalent to a good GCSE grade, are the only requisites besides not having a criminal record.
This is not impossible to study for from scratch in two years, and many town councils offer free Spanish classes.
But not everyone wants to apply for British or Spanish citizenship respectively, and many fear that doing so could cause problems for them if they need to spend an extended period in their native country, such as for caring for a family member."
So many questions remain, such as reviewing the options for dual citizenship where fair appropriate and applicable, greater monitoring and effective regulation correctly identifying place of main residence and tightening of controls to counter tax avoidance (to counter abusive practice from both sides of the channel), option to review the benefit differentials between member states i.e. inequalities that act as irregular "pull factors" to be adequately and fairly re-assessed,...
Presumably this is the OPPORTUNITY to review and develop a whole host of options leading to more effective control mechanisms, so as to attain greater flexibility than currently exists, to respond to the skill needs of the country and more importantly better forward plan and take back control for realistic sustainability of all aspects relating to inward movements of people, retraining of nationals, etc whilst countering abusive practices which lead to downward spirals of income and workers rights (given the realities that have arisen as a consequence of swift irregular patterns of migration), fair contribution of tax and receipt of benefits, health insurance where appropriate and fair, pension contributions and assessed rights for index-linking of pensions, etc.....
What better time than now to reassess and counter abusive practice from whatever quarter it may arise, to review and better deal with differentials, to better plan for the future, but equally attain a fair system that recognises and balances citizen rights with realistic financial commitments/obligations/contributions to the member state where citizens reside?