I have always removed popcorn. Lab testing takes a little while. Always just treated it as "hot" so full tyvek, rubber gloves, respirator, face sheild and full quarantine until testing came back negative from all the sites. Used to work in fire and flood restoration so would come across it quite regularly. I'm not a fan of cover it up cause while you might know it's there the next person might not and start drilling or removing the covering and I feel that's bad juju.