You will have to cut the bv from around the coral leaving some inside the animal! Depending on the compatibility of the rock it was placed on, the bv could have been removed at 4-8 days and by 2 months the "head" would already have formed to make it look "mature"! Sorry they didn't tell you this at the meeting.
I use an elastic crossed over in the middle of the cutting to hold it in place on four points. When the coral has grown around the elastic, it has also attached to the rock. Then just snip the elastic on one side next to the coral and pull it out from the other side!