Loading and Offloading: A transport can load cargo in friendly sea zones before, during, and after it moves. A transport can pick up cargo, move one sea zone, pick up more cargo, move one more sea zone, and offload the cargo at the end of its movement. It can also remain at sea with the cargo still aboard (but only if the cargo remaining aboard was loaded in a previous turn or was loaded this turn in the Noncombat Move phase).
Whenever a transport offloads, it cannot move again that turn. If a transport retreats, it cannot offload that turn. A transport cannot offload in two territories during a single turn, nor can it offload cargo onto another transport. A transport cannot load or offload while in a hostile sea zone. Remember that hostile sea zones contain enemy units, but that for purposes of determining the status of a sea zone, submarines and transports are ignored.
A transport can load and offload units without moving from the friendly sea zone it is in (this is known as “bridging”). Each such transport is still limited to its cargo capacity. It can offload in only one territory, and once it offloads, it cannot move, load, or offload again that turn.