From my monitoring of the system, it appears some patch TGs are "on-demand", where a subscriber to the system affiliates to the TG, and other patches are constant. I could be wrong, and they are all "on-demand," and there is always someone affiliated with it. The NYSTA patch, Buffalo PD patches, and something else, maybe both ECSO patches (on the Perrysburg site, but encrypted), always seem to be on.
I'd imagine Saia does not patch constantly every possible thing that their system does have the capability for, as that would eat up their available slots and limit system resources for other subscribers. It would serve little benefit to them if any.