Per the AJC,
As for the Thursday date, the Tech athletic department will have several on-campus sporting events taking place the next day – baseball, men’s and women’s tennis, track and field and the NCAA women’s swimming and diving championships – that would make holding the spring game on the same night a logistical and staffing challenge.
Moving the game to Saturday would free it from some (but not all) of the on-campus scheduling conflicts, but it would also keep football players on campus for an extra day entering spring break.