well so my plan was to get 100 labs
but i could jsut afford 95
well so i made 3 groups with each 20 labs and than i asked to get 5 more labs
well well someoen got me the labs (i think Vee) so those 5 labs replaced the 35 labs i already owned
maybe it was because the moment he gave me the labs i tried to asign the labs to a group.
here some logs if you need
Edit:
Ok made a quick test. If you give units to someoen who already have a unit of that type in his owned units they will get replaced.
so if someoen has 10 labs and you give him 1 his 10 labs get replaced with the 1.