Is this a re-use of the old code or new code using the old system? If it's new code, how about a combination of the two?
Have factories near the rear (representing a country's industrial base) with cities throughout the map representing distribution hubs. The closer a base to the distribution hub, the faster it gets resupplied (assuming the city / distribution hub is operational). Destroy a city / distribution hub, supplies have to come from the next closest one. Some percentage of supplies goes to rebuilding the distro hub, thus increasing the down time of the fields. Destroy a factory, all distro hubs are affected for that commodity.
Rebuild times are dependent on how much damage needs to be repaired, how much a convoy can carry, and how far the field is from the nearest distro center. Trains run from factories to the distro hubs, convoys from the distro hubs to the fields. Trains and convoys depart at some regular intervals and have travel times based on the distance to be traveled.
If time intervals for travel is too great, some partial functionality (for example fighters with 75% fuel and no ords) could be re-established at a field after some fixed amount of time while waiting for full functionality of the field to be restored.
Lots more details to work out, but I think this gives the general idea of where I'm thinking. Now, if this is simply re-inserting old code, disregard!
Regards,
Hammer