Mon Feb 16, 2015 5:02 pm
If the force that is drawing the supply is within rail range of the depot itself, the supply will go right through the level 1 town along the rail directly to the force. (Actually the force will first deplete the town, and then the depot will send the rest AND replenish the town, but this is transparent, and it will look like your force is just getting plenty of supply and the town supply isn't changing.) Think of it as a circuit being completed between the depot and the supply wagon.
OTOH, if the force is not in range of the depot, but is within supply range of the level 1 town, which in turn is in range of the depot, then the limiting factor is the amount of supply the level 1 town can accept from the depot per turn, which is small (the pipeline gets bigger the larger the town). In this case the circuit is between the wagon and the level 1 town, but the town can't get enough supply from the depot to feed the troops.
This is all assuming that the force has a supply wagon, and you have adequate rail points. Forces without a supply wagon MIGHT be able to draw supply from a depot they are in range of, but that range can vary a lot and doesn't always get to use rail movement rates, so don't put yourself in that situation and instead use wagons liberally.
If you are using your level 1 town as a forward base of operations (i.e. you are using it as the place your force draws their supplies from because they are beyond the range of the nearest depot) then the town will probably not be able to get enough supplies from its depot to adequately feed your force unless the force is very small. You will need to build a depot there, and once you do the supply problems are solved. I put depots in forward locations anyway because they also help stacks recover from battle quickly and so increase operational effectiveness in the area.