@tmartin if the sea battle fails and the Transports weren’t hit during the combat,
at the beginning of the next Round,as the attacker, you can choose to retreat the Transports. They can retreat one SZ from which they came into the battle . There might be 2 or 3 options , depending how many routes were taken to arrive at the SZ.
The units that were going to unload would still be on the Transports , of course .
It would be up to the other side to attack them on their Turn and try and sink them .