Enlistment Contracts in the Roman Army

[Lothia]

Ave Civitas,

I have questions about enlistment in the Roman Army.


+ people (meeting certain physical and civil status) [slaves could not except under dire conditions] could enlist.
+ some were conscripted forcibly. - that I take to mean "Shanghi ed"
+ there was a bounty for recruits - So there must have been bounty-hunters too.
+ a bronze diploma was issued upon completion of a set number of years (depending upon when) certifying discharge.
+ the diploma cited the priveleges earned upon retirement from the Legions.
+ discharge diplomas can be issued for medical reasons.
+ soldiers have been mustered out for retirement (settlement) enmasse when a legate/emperor deems it convenient
+ soldiers can be kept beyond their required year limit for retirement
+ There were some forged discharge diplomas too.

:?

In the Rank and File:
+ does a soldier enlist for a single hitch (3 years, 5 years)?
+ or a single campaign?
+ or until his legate releases him?
+ or Until he has completed the required years to qualify for retirement?

:?
+ Are the same enlistment restrictions applied. that is,
+ Does a Tribune bind himself for the same time span as a line soldier?
+ Are there service committments that must be made once a soldier reaches a certain rank.
(Once made a Centurion he is comitted to remain until retirement)

Thanks again for your help.

Me.