This is what I have gathered on formula vs breastmilk. 0-3 months, bf babies tend to gain more rapidly. 3-6 months things swing a bit the other way, 6-12 months ff babies gain more.
I think bottle feeding *can* mean babies are overfed and trained to override the natural 'stop' signals when they're fulll, which may be one reason ff babies are more like to be obese as adults. But I think diffrences in content also makes a difference - the fats etc are totally different.

Anyway, interesting study, thanks! I presume if there is a difference it must be due to the delivery.