I have found similar "spots" on my BP's chin twice. First was when I rescued him from an uncaring home, and second was while I had to give him antibiotics (unrelated to his chin) every day. Both were very stressful situations for him. His mouth was inspected by a vet both times, I was told there was no signs of mouth or scale rot whatsoever. I had witnessed him doing some face rubbing, so I came to the conclusions that the spots (two) on his chin were from the rubbing due to stress. Takes 2 sheds for them to go away completely.

I'm not a pro, but perhaps your snake has been doing some face rubbing due to the stress of moving? If it were me, I wouldn't start worrying just yet, and definitely check for anything sharp in his enclosure as BPelizabeth suggested.