TL;DR: On-hand rail is produced by railyards depending on national commitment (relevant for smaller scenarios or Axis in general) and turn in game. Reserved rail for units is taken out, giving a final amount for supply, default 90%. 75% of the supply amount is in parallel allotted for Soviet factory railcap. Reserved rail for units then gains a bit of change, depending on something.
1. What happens if rail needed (for supply, presumably?) is not met? There does not seem to be a Soviet rail multiplier for supply in the unit supply screen, for example. Does this only affects supply/fuel reaching forward cities?
2. reserved rail seems to be conked. There seems to be an undocumented baseline of ~1000 unit rail capacity "free" that's added to reserved rail. (Kind of confirmed, Road to Minsk gives ~1600 german and ~3300 free soviet unit rail. After digging, it seems like this free rail is a multiple of the difference between needed and free rail, more research needed. Could be a wrong formula reference somewhere?)
Also: comparing scenarios, it looks like the national commitment % does in fact matter, but taking that into account makes the capacity per railyard point a not whole number. Irrelevant for final calculations, though.
Note: blabbering at night, may find time to revise this to a more presentable view.
v1.12.02 Feature #4:
Soviet factory evacuation will now use separate rail capacity, equal to 75% of rail capacity available for resupply operations (which is equal to total rail capacity minus rail capacity reserved for unit transport).
#5: Increased rail capacity by 10%.
Also: Soviet rail-cap multiplier for 1941 is 5 (2.5 in June turns). Edit: this is wrong, it's now 3.5 in June and 7 in 1941.
In-game example, road to leningrad soviet turn 1.
30429 rail on-hand, 49913 needed, 27386 free (54% met)
F2 strategic view railcap: 4106 unit, 20540 factory.
Production screen shows 10% reserved rail (for units) and 304 railyards.
Here's how the numbers crunch out (I think).
304 railyards are making ~100 railcap units each for 30,400 rail on-hand.
10% of on-hand rail is used for units, so 90% * 30,429 is 27386, which is free.
75% of the free railcap (27386) = 20,540 rail for factory.
The other 27386 (separate?) meets 54% of the supply but is not subtracted out.
54% met means that for supply, 27386 free rail meets 54% of 49913
The 10% reserved for units, 3042, turns into 4106 somehow.
Soviet turn 2:
30,429 on-hand, 98469 needed, 27% met, 27386 free.
4216/20540 unit factory relatively the same. 26% national commitment which does not seem to be working
Changed to 25% reserved
Soviet turn 3:
60,858 rail on-hand, 102,611 needed, 45643 free, 44% met.
16205 units, 34233 factory
So this turn the PRODUCED rail doubled. So the rail capacity multiplier (from 2.5 in June to 5 otherwise) applies at the initial step.
304 railyards making 200 rail each. 25% reserved for units, so 75%, of 45643, is free for supply. 75% of THIS is the 34,233 factory capacity.
Now, for units, 25% of 60,858 is 15,214, which doesn't match up to the 16,205 for units.
Turn 1, this was ALSO off by ~1000. So it looks like it's possible there's a base ~1000 unit allotment plus the reserved rail percent, for soviets at least.
Axis turn 1 skipped because no logistics.
Axis turn 2 (no axis multiplier)
56430 on-hand, 60,796 needed, 50,787 free, 83% met.
Unit railcap is 6656, expected to be 5643, so ~1000 difference.
342 railyards, 10% reserved rail, 23% production from Germany in this scenario.
First line of numbers makes sense. Second and 3rd do not at all.
Axis turn 3:
56430 on-hand, 79452 needed, 50787 free, 63% met
342 railyards, 23% commitment, changed reserved rail from 10% to 40%.
7019 for units, expected to be 5643, or difference of ~1400.
Axis turn 4:
56,430 on-hand, 87,432 needed, 33858 free for supply, or 60% of on-hand.
23605 available for units, as opposed to the predicted 22572, for a difference of 1033.
< Message edited by eskuche -- 3/5/2020 4:14:02 AM >