Stacked Booster Candy Crush

As you beat levels in Candy Crush you stack boosters. Is there a limit? For instance, I often replay level 1 (over and over) up to 8 times to stack boosters and then use them on the 400 Level rounds. I can’t figure out if there is a limit (like if I play level 1 ten times in a row, am I wasting my time? Did I stop stacking boosters at the 8th play?)