From: Berlin, Germany
I guess this comes from HQ distance & unit distance combined? HQ gets maximum supply when it's 10MP from railhead (20MP the MP supply multiplier is still 100%, but within 10MP of the railhead it can get extra supplies), and the unit needs to be 20MP from the HQ.
There are multiple phases for units to draw supplies:
Unit within range of its first level HQ:
1. Draw from HQ stocks, no restriction except the stocks in the HQ exists AFAIK.
2. Draw unfulfilled need over the HQ from the railhead, using the position of the HQ for all range multiplier calculations, the distance HQ-unit does not matter here (it has to be within 5 hexagons/20MPs to the HQ to be in range of it though)
3. The HQ now counts how much need wasn't fulfilled in phase 2, and stockpiles this unfulfilled requests for the next turns phase 1 (this is also subject to reduction due to range multipliers)
Units out of range of their HQ:
1. Draw directly from the railhead, using their own position for the calculations, and requesting only 1/2 of what they would like to!
If there's shortage of vehicles in the motor pool, you'll get (5*(10MP-distance to supply source)% less penalty from vehicle shortages, that's really a big factor if you're in bad motor pool situation. For example, if you have 100k/200k vehicles available, you'd get 50% supply reduction. Being in the same hex (0MP) with the HQ would however completely mitigate this effect. Anything over 9MP and you'd get the full 50% penalty.
Not sure about the motor pool modifier, AFAIK it is simply Trucks availaible/trucks requested, but I am not sure here.
Unit's that have moved will also get a penalty to their received supplies maximum amount, and that's dependant on the distance to the supply source (HQ or railhead). Exact formula is (95-distance to supply source). So the closer they are to HQ, the more supplies they can get.
According to a quick test I did this supply reduction from movement is in fact a mistake in the manual ( I believe it was also confirmed by morvael but I don't want to quote him with something he might not have said)
It's not all that simple :D
@Dinglir: The attempt to calculate the MP of motorized unit is a very difficult/impossible task because you never know how much supplies are in the HQ. But as a rule of thumb, all within 13-15 hexagons/30-40MPs of the railhead will give full supplies, assuming HLYA is doing it right
(and given that he played the Axis side a lot I would bet my best panzer division he does).
< Message edited by EwaldvonKleist -- 1/12/2018 2:45:03 PM >