Day 1: a1-a3/b1-b3a2-a4/b2-b4a1-a2/b1-b2 Day 1: a1-a3/b1.
The next day: A3-A4/B3-B4 A4-a1/B4-b1A2-A3/B2-B3 The next day: A3-A4/B3-B4 A1-A2/B1-B2.
Day 3: Group A, Group I-Group B, Group A, Group II-Group B, Day 1 and Day 3: A4-A1/B4 -B1A2-A3/B2-B3.
Day 4: Three or four finalists, one or two finalists. Day 4: First in Group A-second in Group B, second in Group A-first in Group B.
Day 5: Three or four finalists and one or two finalists.
It's best to draw lots first, because A3, A4, B3 and B4 all have only one home game, and A2/B2 and A4/B4 play back to back.
If it is a full-court game, one session is 10 minutes, and there are four sessions in total. It will take more than an hour for a game to stop.
If it is a half-court game, one session is 15 minutes, and there are two sessions. A game of more than 40 minutes without stopping.
A stadium can't be played in four days unless the 12 group match is played in one day and the elimination match is played the next day.
Personally, I suggest playing for five days and playing for three days in the group match, which can avoid back-to-back and be fairer.