I try not to leave Iris any longer than 3 hours. I guess I'd change her every 2.5 during the day. She can be a heavy wetter, so leaving her longer than that would mean a full change of clothes. We use fitteds and pockets. For pockets, I use a combination of hemp (some 6, most 9 layers) and MF (3 layers). But I'm in the process of changing all our MF to bamboo to try and get a little longer between changes.