Are they housed as a pair? Time to separate them. This will only get worse. We recently had a lady join the forum and I told her the same thing. 6 weeks later she came back asking what to do about the injuries to one of her tortoise. It appears the humper had literally bitten off the tail and as much of the rear legs as it could reach. It was really sad. Don't let this happen to yours. They are telling you loud and clear that they cannot live together as a pair any longer.
And by the way, your tortoises are seriously gorgeous. Nice job raising them.