The tooltip for each will oddly comment on the experience of player units and separately describe each militia units origin zone.
As an aside, despite the game's other commands denying upgrades, the player can upgrade militia units and reorganize them via a SHQ. It requires moving the militia unit back to the SHQ and transferring models into the SHQ first.

Device is Windows 10 Pro 64bit, version 2004 (v19041.421), Intel i7-1065G7 1.30Ghz, 16GB RAM. It is a Surface Pro 7, connected to 2560x1600 display monitor via USB-C. Intel Iris Plus integrated graphics.
For reference, Game Build v 1.05-beta1; Scenario Build 1.05-beta1; Last Game Build used 1.05-beta1; Scenario Version Number #53.