It has been previously speculated that the fourth number is the frame. I believe it cycles from 00 to 29, which would be 30 frames per second (FPS). The third number definitely ranges between 00-59, as you can witness it change from 16:11:59 to 16:12:00 during the cinematic. It only seems natural that these are timestamps in the form
hours,minutes,seconds,frames.
The timestamping begins at 16:11:09.
Sometime at (or shortly after) 16:11:22:17 the time resets to zero as the slipspace rupture occurs.
0:45 into the cinematic you can clearly read:
> POST SCAN CAMERA ACTIVE
> SCAN>>POP:0
> [EVAC.COMPLETE]
The footage resumes with a drop pod crashing at 16:01 - a time earlier than when the cinematic began.
The drop pod crash causes the time to reset again to zero. Around 0:51 it appears to read "TIME ANOMALY DETECT" and then "RESYNC GMT", and the time appears again (16:11:50-ish).
At 1:22 into the cinematic, we see the text "MAINTENANCE INTERRUPT [22:02:20]" and the timestamp in the lower right corner matches. 10 seconds later (22:02:30) the drop pod hatch blasts open and the screen goes dark. (Twiz mistyped this as "22:03:30:04"...a minute later.)
The last timestamp we see is at 22:02. If you assume that's the rookie (despite the drop pod not being lodged into the side of a building), then what is significant about the time 1 hour after he drops?
I'd continue... but require sleep...