In Toronto’s nightlife, there were definitely establishments referred to in English as “After Hours’.”
In the days when liquor could not be served after 1am in Ontario, such places purported to serve only espresso and soft drinks, but there was nearly always some kind of nudge-nudge-wink-wink way to order some kind of alcoholic drink.
The entire 80s decade is a hazy blur to me for some reason or other, but I seem to recall places like “Le Tube” opening at around 11pm, but not getting going until 1:30am when everyone left the ordinary clubs.
(The building that housed Le Tube is now the home to a leather shop that has a large kink clientele. I believe that the things people wore to LeTube in its heyday were at least as risqué as the fetish items they buy in that location today.)
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Anyhow, absolutely these are loanwords from English into other languages like German, but I dispute that “After Hours” is not used in English.