Ambush team:
With above-average tickets, their objective is to deplete the attackers of tickets. They must intercept any suppliers they come across before they reach the defense objective. They do not get additional setup time, but they do get additional bases.
Convoy team:
With below-average tickets, their objective is to deliver a unique supply type from main base to a destination near the ambush team's spawn. All logistics vehicles are disabled during the staging period, but not transport trucks or other vehicles that can only deliver ammo.

For every 20 convoy supplies (food for conventional, drugs for irregular) the ambush team loses 1 ticket. A single logi can deplete a whopping 150 tickets this way, and a technical can score 70.

Convoy supplies can be stored at FOBs to decrease the distance (and risk) necessary to deliver them to the objective. However, if the ambush team destroys that FOB...

Conventional and irregular factions alike can assume either role.