I will happily give way to an aerodynamicist on this but, for what it's worth, and based on my time with the C-141 that also had drooped wings on the ground, they certainly straightened out as lift increased. And the effect of the weight of fuel in the wings should also be considered. I could touch the wingtip on the ramp before departure on a flight of four or more hours whereas, after landing, that wingtip would be way out of reach.