A8 transitional arrangements meant the UK did not have to allow free movement for the new A8 countries (Poland) etc.
that was then.
Currently the UK does not exercise its control of visa overstayers:
Are people who overstay their visa the UK’s biggest immigration problem?
We don’t really know how many people are in the UK without the proper permission. The Home Office doesn’t publish figures on this, so we have to rely on estimates.
The
most recent estimate suggests that around 618,000 people could have been living in the UK without permission in 2007. But because this was an estimate, the study thought that in reality it could be anywhere between
417,000 and 863,000people. Of these
around 442,000 (72%) were thought to live in London.
If the UK dont exercise its control now, please provide any evidence that leaving the EU will make any difference.