not be all day
To not take a long time. Usually used in the present tense to convey annoyance. How long is this repair job going to take? It better not be all day! Run this to the post office, but don't be all day, OK?
(not) be/take all ˈday, ˈmorning, etc. (to do something),
not have all ˈday, etc. (informal) (used as a request to hurry up) (not) take a long time (to do something): ‘Are you going to take all day shaving?’ she shouted to him through the bathroom door. ♢ Come on! We haven’t got all day!