Yea, you can’t off load your ground units until you win the sea battle, so in the case of a scramble against lone transports it is impossible to win the sea battle. Therefore if the tpts can retreat they take their cargo with them.
I agree that if you bridged (didn’t move the transports in the combat move phase), then you can’t retreat your transports. I also agree that is an easy fix, you just point out in the combat move phase the different paths your transports took to get back to where they started lol.
I have to say that although the rules are in place to deal with this situation, it really shouldn’t come up unless you are just learning the game (maybe your whole group is learning). If I was playing with a newbie and they did this (or something similar) I would defiantly point out the error. Nothing like playing a game for hours (days) for it to come down to some BS where he looses 10 tps because he missed something that should have been obvious.
I just don’t see why you would ever take in lone tpts for an amphib, unless you were facing Japanese Kami’s (exposing surface warships), but you would still flood the sz with air to protect your tpts from scramble. If you can’t get warships in (maybe they are blocked, but can NCM in later for protection) then you still send air units into the sz to combat the possibility of a scramble. I could see getting diced and losing your escorts/air leaving you in this situation, but not setting up for destruction from the get go w/o any cover.