My method of controlling filament moisture is based on weight, detailed here. I’ve now have an Eibos dryer, but the only time I print directly from the dryer is with TPU and PC, or maybe PETG if I expect to be using the same spool over several days.
I tend to be a bit obsessive about printing with dry filament, but PLA is slow to absorb moisture and the material I worry about the least. Though I’m in a humid climate, I can leave PLA out for at least a week or so (no AMS) without moisture problems. (In that case, I do dry it again before storage.). I don’t worry about one or two grams of moisture weight gain, six grams or more definitely calls for dryer time.