Upvote:7
Can he enter the UK on 19th Nov?
Yes, though given the answer below it may not make much sense (and of course any plans must match what is allowed).
If yes, then Immigration will give a stay for 180 days or only for 1 day?
According to The Immigration (Leave to Enter and Remain) Order 2000, Part II, Article 4:
Extent to which Entry Clearance is to be Leave to Enter
4.β(1) A visit visa, during its period of validity, shall have effect as leave to enter the United Kingdom on an unlimited number of occasions, in accordance with paragraph (2).
(2) On each occasion the holder arrives in the United Kingdom, he shall be treated for the purposes of the Immigration Acts as having been granted, before arrival, leave to enter the United Kingdom for a limited period beginning on the date of arrival, being:
(a) six months if six months or more remain of the visaβs period of validity; or
(b) the visaβs remaining period of validity, if less than six months.
(...)
So they can only stay until 20th Nov 2022.
This is different from the situation in the US where you can enter at any time during the visa's validity and still get the full duration.