There are airports which, if you are on final when they close, will tell you that you cannot land, and you have to divert.
I think it's pretty common, and is connected with "somebody" having to pay ATC and fire crew a massive amount for overtime if one goes past even 1 minute.
Turning off the lights is pretty mean but is really the same as not issuing a "cleared to land". If you wanted to land in that situation (no clearance) you would have only some seconds in which to notice "low oil pressure" and declare the mayday
I come back to what I said earlier i.e. if unlicensed then the solution is easy. If licensed then you rely on the CAA to sign you off, which they don't have to do. But who needs to be licensed? It is surely only for AOC ops these days?