Probably already aware, but, have noticed the general pattern for people recently/currently onboarding to SARA has been basically been this, AXY12, a "type" (A), then the county number (XY), and then just (sequential?) sequencing (12). Earlier adopters don't have the same pattern
Story County's "types" generally shuffle out to 1 being interop, patches, etc. 2 is law enforcement, 3 I haven't pegged down, but the university has a bunch of maintenance and residency channels, fire talk channels, and a couple non-university security that I haven't figured out who it is. 4 is fire, 5 is public works.
18502 - VLaw31 patch
28501 - Story County law enforcement
38535 - ISU something
48505 - County Fire Tac
58501 - story county roads
With every rule there is an exception......