We have a 7 month pup and he's huge, about 22-23" at the shoulder, and must be about 35kg. We have come across a few other pups 4-5 months older than him and on one occasion he was double the size of one and quite a bit bigger than the others. Only this morning on a walk a couple of other dog walkers couldn't believe he was only 7 month lol. He's already to powerful for the kids to walk alone, and the wife struggles with him sometime. I know no one can say for certain but is there much more growth to come.
We have a neighbor that has had 3 Labs all well over 100#, probably close to 140. They looked like giant versions of a bench style dog. They came from different kennels, but the owners seemed look for big dogs.