I'm a bit curious, this was posted in the patch notes.

Individual Contributions
Players of all four disciplines can contribute to a hamlet militia’s supply caches, with rewards given based on the type of contribution.

Disciples of War and Magic
Completing level 45 caravan escort duty will benefit the corresponding hamlet’s supply rating.
Does that mean that since only hyrstmill is currently implemented, that only people who chose Twin Adders as their GC can participate in the caravan escort during the non-combat phase? Or is it a caravan escort separate from the GCs