Given his 6' 2" (w/o shoes) frame, with his long (6' 7.25") arms, it's not at all unreasonable for him to carry 196 lbs.
The question of whether he has gained 16 lbs in just 12 weeks is maybe just begging the question of whether he was really 'only 180' at the end of last season.
Just because his player weight was listed as 180 to start last year doesn't mean much. He could have been much lighter or heavier than that at various points in the season.
He's young and at an age when he is probably continually adding muscle mass. If he started the season at 180, I can easily believe he was over 185 by season's end.