What’s your level? I’ll be very very surprised if you’re an associate. When I worked at a big 4, the associates didn’t leave until after the senior associates, who left after the managers, who left after the senior managers (if they were around), etc. The reverse was true in the mornings. Because we were expected to maintain appearances. I didn’t play that stupid game (as a sr assoc) and definiely heard about it through back channels.