The plastiflimsies tend to be personnel and inventory manifests and so
on, mostly talking about who moves where. The CDs are monthly data
hardcopies. This wasn't the Guard headquarters, that was clearly a
place somewhere mid-crater. Guard activity is moderately low through
2439, at which point the Guard seems to go on hold (and pieces start
getting moved around and off-planet). From the lag times and
equipage, plus what you already know, it looks like this is when the
war against the outworlds starts. Ridena is generating support and
training, whereupon the units go outworld. From the point of view of
the Guard, it looks like Vietnam. It's supposed to be easy, in and
out and push over the low-tech opponents, but it ends up being a
terrible quagmire into which guys keep being thrown. Then, in 2448,
it's not just the outworlds; there's an inworld rebellion that needs
to be quashed as well. Ridena isn't in rebellion, so it's still
behind the front lines, as it were. The outworld campaign appears to
be scaling back but doesn't completely drop out. This continues
through 2450, as the rebellion seems to be gaining political ground
but losing military ground.
Then, it gets confusing. The Guard seems to be getting a new set of
orders in addition to the old ones. It takes a while to figure out
what's happened here, but eventually you read between the lines and
get that the new set of orders is coming from the Hegemon, rather than
the Strategos; he's thrown in in support of the political objectives
of the rebellion, but the Strategos hasn't backed down, and it's civil
war. The Guard who are on Ridena at that point dither over this a
little while, but does end up on the side of the Hegemon. They're
still "behind the lines" at this point, but in 2453 the civil war
comes to the system. The Guard is actively involved in some fighting
at this point; they coordinate with the Legions here, and with some
small number of Skyguard, and then as of 2453.155, there is nothing at
all.