I've read the manual, and I am making these statements just to make sure that I interpreted it correctly. Am I correct?
1. Low fuel can only be established or rectified on the midnight turn.
2. Low ammo can be established or rectified on a turn-by-turn basis.
3. When using explicit supply, the only way with low fuel/ammo can be rectified is if a unit is within the range of a supply unit (not in travel mode).
Point 1. I think you can only become low fuel on a midnight turn but it then can be refueled on any turn thereafter if you meet the required conditions.