Yes, I think it was the bug which considered as isolated units more than 25 hexes from railhead (there should only be a requirement of more than 100 MP from railhead). This was fixed.
I hope to finish it soon. Tests are positive.
Bug fixes so far:
1. Fixed a bug in calculating supply and fuel required by units resupplying from a HQ, which shouldn’t take into account MP and range to railhead penalties into account. These penalties will be now correctly applied at later step, when actually requesting and receiving supply and fuel from cities. This prevented units to operate more than 25 hexes or 100 MP from railhead, even if they were within HQ supply range, and that HQ was within railhead supply range. Also, this prevented HQs to act better as a buffer, dispensing reserves on hand to units needing them (bear in mind that HQs will still try to maintain some reserves). All other penalties are still applied at the earliest possible step. Supply details window will still show Range and MP modifiers based on unit's actual distance to railhead, because they are taken into account in other steps of the logistics phase (for example: units more than 100 MP from railhead are unable to recieve and/or return vehicles).
2. Fixed a bug in calculating the percentage of required supply and fuel dumps available in a HQ after it was resupplied from a city. Wrong value caused some units to take more than they should, while others were left starving.
3. Fixed a bug where out-of-supply trace could be determined to be better than in-supply trace, leading to isolated units in case of a very long land connection despite having access to port supply. "In-supply" means going through 0 enemy hexes, and not above 100MP and/or 25 hexes from rail.
4. Fixed a bug where on-map units were not rebuilding nor arriving according to reinforcement schedule in scenarios that didn't use entire map. It will be now up to scenario parameter to decide whether unit rebuilds are allowed or not. To prevent unit rebuilds in smaller scenarios, five were updated: Op Mars 1942 Red God of War, Operation Konrad, Road to Kiev, Road To Smolensk, Smolensk 1941.
5. Fixed a bug where the game was unable to load WiteFontConfig.txt file and always used default font configuration.
6. Fixed a bug where units more than 25 hexes (but not more than 100 MP) from railhead were considered isolated.