Latest time for tactic change before match

What"s the latest time to change my tacticts before a match? So my opponent wont be able to react?

approx 4 min

Thanks , hope you are right and i dont do it too late :D

I am right. dont worry. I change my team starting at 5 min and I know i have roughly 1 min give or take to move my players.

God bless you, and may Fortuna be with you. :D