What does BNSRB mean or stand for ?

BNRSB is the satirical opposite of BRB – be right back that is one of the most used short forms used in everyday online chat language.Its used to tell the other person in a sarcastic way that you will not be back fast and not wait up.

It maybe also used in a humorous way between friends when they are chatting to say that they will be late to come on messenger.