I did a 4 week EM (approx 5 weeks from pitching yeast) in May of 2022 and didn't have any issues with mold. As long as you keep the lid shut under airlock and there are no leaks, I do not forsee you having any issues. I've very happy with how it turned out.Are you saying the skins are susceptible to mold even under a snapped lid and airlock?