if you amend an order lets say to buy 50000@ 0.4 and then you amend it to only 40000 it does not.
if you change the price it does But if lets say you want to buy 50000@ 0.4 then you want to buy 80000@ 0.04 then the 50000 and in the original Que and the 30000 go to the bottom but it is only one order,
practicing accountant