Question about Patreon pledges... (Patreon)

.... Hey guys? I'm not complaining or anything, but when exactly do the pledges come through? DO they come in exactly one month after each person pledges? Or does patreon just choose a random date for an assortment of sponsors?

Just asking because I seem to be getting smaller packets of money every couple weeks, as opposed to a large monthly sum.

Again, not complaining, just a bit confused as to how this works.