relatively late to molt
This is an interesting time of year because of the variation in molt that is apparent in male ducks. Some drake mallards are in full breeding plumage while others are just making the transition from basic plumage (cryptic) to alternate (breeding).
This photo that Charlee took a few days ago shows one late bloomer male (bottom duck) flying with a bunch of females. I’d bet most of the flock were hatched this summer.