Cat was overfed by cat sitters and went from 12.2lbs to 13.4lbs. I dropped him back to the amount I was feeding him, and in a few days he's back down to 12.8lbs. Is he losing weight too quickly?

Cat was overfed by cat sitters and went from 12.2lbs to 13.4lbs. I dropped him back to the amount I was feeding him, and in a few days he's back down to 12.8lbs. Is he losing weight too quickly? He's acting normally and still has an appetite.