This question is somewhat related to the question asked by bsartist. If you have a 107 do all of the drones you fly have to be registered under the commercial registration category? If all of your flights are being made under the cover of your commercial license do all of the drones you fly have to be registered as commercial?
That's an interesting twist that I had not thought about. Here is my spin on it and it's just shooting from the hip....
If you have your Part 107 it should cover hobby flights (more restrictive than hobby) and we should be able to fly as a Hobbyist with just our Part 107 being current. So we should be able to exercise both sides of the coin by simply having Part 107 current which would mean flying Hobby Only aircraft under our HOBBY Registration #. That being said until it's codified that's just a HUNCH at best.