The best cure I've come across for an early release is to make sure the left arm continues to lead after impact. A lot of players seem to practically stop the left arm at or close to impact which, effectively, blocks the left side and gets the right arm and hand flipping through / over. This action will encourage an early release as the right hand / arm become the only way to maintain the momentum of the swing.

This should be applied to chipping also; keep the left arm going - you will find you hit more consistent chips with a nice, smooth tempo.