Okie, suppose that NOW IS THE MOMENT OF SPEAK OF THIS SENTENCE.
The party took place AT SOME TIME IN THE PAST. Now I and you are looking at the photographs taken at this party. I run into a photo in which Mr. G was drinking champagne - which is contrary to his habit, so I call you and I say "Mr Gibson usually drinks mineral water,but in this party he has drunk champagne". The implication is (as I have already told): ông ta vẫn thường uống nước khoáng, nhưng không, ông ta đã thay đổi rồi, xem đây thì biết…
See there, ít makes sense, but it doesn't outwit the other solution. Both sentences CAN be correct, I think so.