I’m not sure when to release the puppy tug/sleeve after my dog counters.

Many people are confused by the counter (repositioning the grip to bite deeper into the tug or sleeve). They wait until a puppy (or older dog) counters and immediately slip the sleeve as a reward for a counter. This is a BIG MISTAKE. If you do this kind of training you will end up with a dog that is very mouthy on the sleeve.You are teaching the dog that if he readjusts his grip he wins the fight. If a dog is a little unsure in the nerves he will become very mouthy very quickly. He will think "I ended the fight in the past by re gripping - so I will re grip now. But wait the helper did not immediately slip the sleeve this time - well ---- I will try to re grip again to see if I can get him to do what he has always done in training - which is let me win the sleeve and he goes away.The correct way to do this is for the helper to watch for the counter. When the dog re grips deeper into the sleeve the helper takes up slack in the leash to set the grip and then takes a few steps on the outer edge of the bite circle to allow the dog to settle into the grip.

If you always do your training in this way the dog will learn to be comfortable in his grip and understand that he must settle into a solid grip to get his prey item (the sleeve).