Advanced Tactics is a versatile turn-based strategy system that gives gamers the chance to wage almost any battle in any time period. The initial release focuses on World War II and includes a number of historical scenarios as well as a full editor! This forum supports both the original Advanced Tactics and the new and improved Advanced Tactics: Gold Edition.
First one is that your troops took damage in the form of readiness drops. If so, then that would lead to more supply consumption than planned. Since troops they use up supplies to regain readiness.
Second one is that troops produced are not taken into account as far as I know. These too require supplies, so they can fill up their stores.
I am sure there could be others, but those are just off the top of my head.
Creator of High Quality Scenarios for:
Advanced Tactics Gold
DC: Warsaw to Paris
DC: Community Project.
I go into the Production view. There I select the SHQ. Then I look at the top of the total production. There it says how much production was actually required that turn.
Be aware that when talking about supply it is always a prognosis. It's never a hard number. It depends very much on the amount of readiness loss your troops take, and how many you produce. So always make sure that you have more supply than you actually need. If you don't you may end up in a sort of supply purgatory, where units simply try to catch up getting supplies enough. When that happens you would ordinarily need to get twice as much supply as actually needed.
Creator of High Quality Scenarios for:
Advanced Tactics Gold
DC: Warsaw to Paris
DC: Community Project.