Hey guys... so, I just realized that this is the first case where a retreat is necessary and I haven't really explained how retreats generally work. So here goes:
When I prepare the map, and there are retreats necessary, I will do one of two things:
1) If the unit has more than one place it can go, I will simply take the unit off the board while the player needing to retreat makes his choice.
2) If there is only one place for the unit to go, I will move the unit there, but the player in charge of that unit still needs to confirm that they want to retreat (because off the board is an option).
So, if, during the course of the game, you need to retreat, please do so. If no retreat is received, the assumption is off the board (so you will lose that unit).
mvp