It will still be a while before this is directly observed.

We're fairly sure that it "falls" downwards for a wide range of theoretical reasons and also due to the 1987 observation of gravitational lensing in neutrinos and antineutrinos from a supernova. If we observe the opposite in a lab then it will be incredible because we'll have to reevaluate a lot of what we think we know about physics. If we observe it "falling down" then it will be an important result but not at all revolutionary.