I don’t know if this game will have a main destroyable objective, that if destroyed will win the game for the attacking team. But, if it will, do not make the same irritating mistake you guys did with it in quake wars.
In quake wars, you plant a charge and after about 40 seconds, it blows along with the objective. But, if the time remaining for that map was less than 40 seconds, the attackers would have lost anyway because the charge would not blow. Well, that’s a total waste of 40 seconds if you ask me.
This is my solution: make the timer stop to 0 if a charge is in place and only end the game if ALL the charges have been disarmed or ONE blows. People can still plant additional charges during this time. Except for stopwatch mode of course 

