There's a lot you can do at home to set the stage, but it's all for not if not maintained when hunting. Otherwise, Pup will quickly assume different rules apply then. One way or another, correction will have to be as consistent when hunting as in training or you'll have a breaker.
This coming from a fellow who's dog has six seasons and better than 7,000 birds under its belt but got loose on his line manners this season because it was "easier" for me when we had paying quests with us to let him roll on tipped birds a couple of times than to call him back to the blind and make him handle them correctly. Should have sucked it up, said, "Sorry, guys, I can't let him get away with that." and nipped it in the bud, rather than paying the price of vigilance and more apologies over a longer recovery period, because I let him slide the first time.
If you think I'm wrong, you might be right.