No way.. System will automatically assign qty (based on your removal strategy)..
Suppose you have parent, child location:
Stock and Stock/Provision then system automatically check qty in both location and automatically assign but after assignation if you want to change source location then its possible..
Also if the whole qty assigned from one location(Stock) now if you want to assign some of qty to another location(Provision) then you can use the split functionality and reassign source location..
See here : https://www.diigo.com/item/image/5ony4/p51i
Thanks..