Too many Qbu 191 than Qbz 191 in promotional photos and videos. What is the realistic ratio of these 2 rifle in the unit composition in the future ? BTW if PLA really like QBU design to QBZ, they shouldn’t had penny pinched on a little extra cost.
In those pictures, they are standing in rank and file, meaning that each position in each row the person of each role will hold the same weapon.
We are being shown the unit from an angled photo gallery where we happen to see the designated marksmen of each row, but we can also see others carry the LMG and standard QBZ-191s.
I'm not sure how you can make a guess of how many QBU-191s there are in this unit based on those photos alone, but I bet if you zoomed out it would be a standard composition.