OK, why do I have parenthesized supply values?

[Elessar2]

No joy in the manual. It's frustrating as heck to check the predicted supply, next turn comes, but no, instead of the 7 that was promised, my HQ shows this bizarre 4(7) supply rating, can't reinforce or upgrade my troops. Is there a tech somewhere that I am missing? Am I assigning too many units to the HQ? [this happens to my Germans too, topped out in C&C for a good while now]

[Sugar]

If it shows 4(7) the HQ receives 4 supply and provides 7. You'll have to calculate additional distances between the HQ and the unit; the amount of supply units receive depends on the movement costs of the hexes between the HQ and the unit's placement. BTW, afaik a distribution of 4 supply shouldn't generate more than 6, but that may be related to the version you're playing.

It`s best to leave one HQ in the next city/town/capital/near port; as long as that ressource shows 5, an HQ placed there will provide 8 supply, and the units in the next 2 hexes wll receive 6 resp. 7 supply which are needed to fully reinforce/upgrade/overstrength.