Found this - could be helpful for some (and me).
To those new here, a call-out is when you are using a headset and can inform your teammates where enemies are by calling out the specific location using keywords/descriptions. Makes the game WAY more fun and productive.
That link above, has each map with the call-out shown above each area.
Someone should make callouts for shipment, i always get lost in that map.
for hijacked you just need to shout "CLUSTERF*CK" and you'll know to head to the the middle
I get dizzy with the spawning of that cluster of map.