This one's going to be a doozy, so try to keep up.
There will be two Percussion/Winds Power Regionals (East and South), plus a "regular" percussion/winds regional down in Atlanta. For the color guard division, there will be three Power Regionals—Mid-Atlantic near Charlotte, East near Allentown, and Southwest—the latter of which will be split between two venues.
300+ Groups will take the floor this weekend in preliminary performances alone. About half will move onto their respective finals competition on Sunday—ALL Power Regional events are two-day events with prelims on Saturday and Finals on Sunday. Atlanta will just be one-day, though.