Supply - Situation

[Mowgli]

Hi! 

In my recent PBEM, me and my opponent had a supply situation we couldn't quite understand. We are still learning, so maybe you can help us out? :)

Here is a picture of the situation (Sicily 43, alternative "Gruppo Mobile E" scenario):



The Americans (green counters) try to get supply from the beach ("supply sources") over the bridges ("bridges") into Gela ("supply destination").

The Italians (yellow counters) try to cut the supply line with their tank units. Now, the Italians have all routes within their ZoC. However, the Americans have a chain/corridor of units running through the Italian ZoC (green X), so the supply should get through? But in the game, all units in Gela are isolated (except for the Rangers, who are immune as they're "commando" units).

• One idea is that the HQ-unit (the green X low right) is the weak link for the Americans? The manual states that HQ-units don't have ZoCs, but from my understanding this does not automatically imply that the unit itself can't "lift" enemy ZoCs? 
  
• And even if the HQ-unit is the weak link, there must be another weak link, as there is another supply source one hex to the west of the HQ-unit! This would indicate that the artillery unit (ordinary field arty) is the weak link?
  

Any help to clear the situation up is much appreciated!

[Mr Grumpy]

Are there actually bridges crossing the river where you have placed the yellow rectangles, I can't see the map underneath to check.

I am sure you can trace a LOS from unit to unit and friendly units (even HQ's) do negate the Italian ZOC, so I am wondering if the river is blocking the supply into Gela as you can't trace a LOS across an unbridged river hexside.

[Mowgli]

Are there actually bridges crossing the river where you have placed the yellow rectangles, I can't see the map underneath to check.

I am sure you can trace a LOS from unit to unit and friendly units (even HQ's) do negate the Italian ZOC, so I am wondering if the river is blocking the supply into Gela as you can't trace a LOS across an unbridged river hexside.

Yes, both of the indicated bridges are "heavy bridges" and fully intact.

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Now that I think of it, "isolation" was determined at the start of the Allied player's turn. The screenshot, however, was taken at the beginning of the Italians' turn (I'm playing as the Axis). So the situation might have changed as the Allied player has moved his units. But I'm 100% sure that the engineers and the arty unit were NOT moved during his turn. There is an easy way to find out: I will see if his units are still isolated in the upcoming turn. I will report back!

[Mowgli]

Update: All problems solved/explained! I feel a bit silly now. I've messed up the positions of the supply sources in the picture above. Here are the real locations:



The HQ unit (marked with the red X on a green background) had moved here during the American player's turn. So it was not present in that hex at the start of the American turn, which meant that the tank unit's ZoC did block supply. 

Now it's my opponent's next turn (so the situation that can be seen on the screenshot actually applies) and his troops in Gela are no longer isolated. 

Sorry for all the confusion! I hope this example can help other newbies! :)

[Mr Grumpy]

No problem, their are no stupid questions when you are learning a new game system.