Residency acts of law comes from EU and are permanent as per “you live here and like to stay that way”;
UK “Right to remain” you have right to stay as long as you keep RIGHTS to do so, if not, you are hunted down by HM Home Office and HM Borger Agency to be expelled from UK on your cost.
One of them is to not be in employment status over 24 months…. Regardless of Limited or Indefinite.
Rights are given and taken as admin power see it fit.
PS. UK Passport and British second citizenship can be taken away too
so my analogy to taxes: ALL DIFFERENCES ARE IN DETAILS….