Since May’s introduction of the hostile environment universities had to build up a complex bureaucracy to track visa compliance if overseas students. Even research activities such as short term academic visitors or overseas examiners for PhD exams have become more complicated.
Universities are regularly checked and accidental non-compliance with visa rules even in small cases have the threat of severe penalties over them.
Yet, the businesses who thrive on illegal workforce are well known. From time to time there are show raids to arrest the workers. But the companies themselves rarely have to fear consequences. I guess it is one rule for universities and another rule for CEOs with deep pockets for party donations.
Ah visa regime...sorry I missed that