I keep and extra cup for running raw thinner through the gun after each day of use. The laquer can sit in the cup for several days provided you put the gun back on the cup and shove a tooth pick in the air bleed hole in the top of the cup.
But you said you are using a jam gun and those don't hold much laquer so if I were you I'd clean cup and gun every day.
As others have said that top looks killer.