sealing it up is dangerous at times, but if the RH is stable at 50%, then you are probably fine to seal it up... 55-62% is the range ppl suggest.
at this point it's just about getting moisture to equilibrium in the plant mass and at low enough levels microbes won't grow on it.. i don't think any chemical changes are occuring to the THC unlike curing tobacco, from what i know...
anaerobic growth is bad.. avoid it. weird smells come from this. if rh isn't rising anymore while curing, you don't have to burp as often.... but still do occasionally to avoid brown weed that smells like shit. (lack of o2 will cause greater loss of color than normal and grow anaerobic bacteria - might smell "pickles" or worse)
the less i follow the groupthink and the more i rely on my education of certain topics, the better my curing has gone... YMMV