Girls trip + Pumping

Ga

Hi mamas! I am going on a vacation with a few friends in January. Baby will be almost six months and likely eating every four hours during the day then. Since we will be out and about, i am going to need to pump on the go it seems. Does anyone have experience with this and if I go a longer stretch than 4 hours will my milk decrease or as long as I get four pump sessions in I’d be ok? Thanks!