1
general::
Phrase(s): after hours
after the regular closing time; after any normal or regular time, such as one’s bedtime. • John got a job sweeping floors in the library after hours.
McGrawhill's American Idioms And Phrasal Verbs
2
general::
After normal working hours, after closing time; also, after legal or established opening hours. For example, I haven't time while the shop is open, but I can see you after hours, or The restaurant employees sometimes stayed for a meal after hours. This term originally referred to laws governing business hours. It Also gave rise to the term after-hours club, for a drinking club that remained open later than similar establishments. [Mid-1800s]
American Heritage Idioms