Unfortunately for me, I never observed that happening, if it did with my guys?? Puppies are a noisy growly bunch.
If I see that happening and I'm clear on the target and the growling seems a bit over the top..I'm going to assume a dominant dog. And he found the other dominant dog in the pack and is saying "I'm coming for you, if not today give me time!"
I'd stop it cold! I'd get between him and his target firm "NO" play time is over! If it's a submissive dog he won't be doing that, if it's a Dominant dog, he needs to know who's in charge!
I did pack walks with my guys once over two weeks, one Dominant male BullMastiff/Pitt mix and one Balanced Boxer girl and my friends out of control herder dogs one balanced male and one Dominant female.
Intro done, pack walk all is going well and sure enough the two Dominant dogs found each other! Tussle ensued, I broke it up, That was it no more problems (remaining time) the two Dominant dogs gave each other space the balanced dogs never had any issues.
Rocky my GSD was my waterloo in my three dog household. Never saw it coming, 18 months trouble free, then out of the blue??? It was on big time no growl no warning! He starting attacking my male Bully!!
I never got a chance to fix it Gunther passed shortly unrelated to the fighting! But moving froward when Rocky did a low growl at company, I took that seriously and took action no corrections just "appropriate" training and it worked out well!
A Dominant dog needs to respect "all" the members of the pack otherwise he will pick and choose who to respect! Failure in leadership on my part, Rocky never gave "me" any problems..."You can run the ship "I'll" run the crew was his take!"
Don't know if that's any help, but it's how I formed my "opinions". :