Had a young male that had it come up on his left elbow. Of course when I first noticed it I was in a panic.
My vet told me the same thing. Restricted his activity....he was not happy about that......padded the elbow. And though it seemed to take forever, one day I went to change out the padding and it was completely gone. Has never had it come back.
So Belle should get it back in shape soon. Don't expect it to disappear quickly, they seem to take a while. But it should disappear just like it appeared.