In level increments, from low coverage(1) to High (5) plus highlight ( second pass). You can do one White pass as fast as color passes ( in some standard scenarios up to 60 prints/hour excluding pretreat) either 5 or 1 take the same time, higher coverage does not translate in slower print, the highlight can add another pass ( albeit probably not all areas of a design need highlight, unless it is a solid white image), and color adds another pass so the same image might need up to 3 passes to print in a dark garment, the platen needs 1 minute 20 seconds to do a 14x16 art, so I guess you can do the numbers, 10x12 is the nicest to print because it can take around 40 seconds ( on light garment) that is the time needed to dry and unload the previous shirt, so allowing o a very continuous workflow.
see included screenshot