Hey guys, been lifting consistently for about a year now, wanted to share a small win and ask for advice.

First off : got my first strict pull-up today, feels great after months of grinding!!

Main question: dumbbell shoulder press. I can do 10kg per arm for 12 reps easily, but I'm stuck moving up to 12kg. It's not that I can't lift the weight overall, I can get the dumbbells up. The issue is my elbows sit slightly too low/forward at the starting position instead of being stacked directly under my wrists (forearm vertical, right angle). I physically can't raise my elbows into that correct position on my own with the heavier weight so I need someone to nudge them up slightly before I can press. Without help, I just can't get into the right starting position.

Is this a mobility issue (shoulder flexion/external rotation) rather than a strength issue? Any drills to fix elbow positioning at the rack, or is this just something that improves with more shoulder/upper back mobility work? Would lowering the weight and drilling the setup position in front of a mirror help, or is there a specific stretch/exercise for this?

Also open to any other general advice or things you wish you knew a year in. 

Thanks!

1 year in, first pull-up ever + stuck on shoulder press jump (10kg→12kg)