Hey Bar Pharma – Good question man! So if I was at that point and was not making progress I would really nit pick my form. If someone is moving those loads and not growing something is probably off in the execution so I would start there. If there was not an execution issue I would still slow down my reps and find ways to make the reps harder IE slow eccentrics contracting all the way down, pausing in the fully stretched position under load, making sure to fully contract the load through the muscle being worked and not place the load on and off the joint constantly IE knees, lower back ect. If at this point I was not growing still I would look to then add more volume because chances are if I had checked all those boxes and nothing was happening then I would be still be training under my threshold for recovery hence my body seeing no reason to make a change.
Nick – Let me know how it goes!