They may not "need" to eat for another week or more. You may "want" to feed them again in 2 or 3 days. As long as they look plump and healthy, there's no need to feed them. I prefer to overfeed slightly because it makes me feel better knowing they are eating frequently, but I doubt it makes much difference to their overall well-being.
I feed my slings portions of cricket every 4 days or so. The adults i feed about once a week. I like feeding the slings more often but less food rather than less often and more food, since when they have small portions they dont leave many remains and fungus is not a problem.