Regarding the placement of newly-purchased Legion Battle Units (LBUs).
When you say that "The Units are assigned to the Holding Box of any Legion that occupies a Legionary Camp" does it matter if the Legion occupying that camp is different from the designation of that camp?
Meaning could the XXth legion be in Isca Augustus (the IInd's camp) and still receive a LBU?
The designation is just for set-up and historical flavor. The XX could indeed being in the II camp.