This is a modified version of my "best 2 out of 3" multistage koth logic prefab.
All three rounds get played, the outcome of the first two rounds deciding who gets a time advantage on the third round, or if it is a tie, both teams will have the same time.
Times can be adjusted to fit your needs.
Multistage Koth (Time Advantage) a1
Two rounds of koth to decide a time advantage on the third round.