Yes, the 5A1 post is the A.A. Co. side of Laurel and Maryland City. The post assignments that you see on the map are mandatory to fill with officers, a.k.a., minimum staffing. If there aren't enough officers then a supervisor will beg, borrow, or steal another officer from another district or announce, over the air, overtime available. The day shift and evening shift are allocated more officers and the post assignments, as per the map, are different for them than they are for the midnight officers. For example, during the day and evening shift the 5A1 and 5A2 cars work the Maryland City area while the 5A1 car is the only car working there during the midnight shift. If you're hearing a 5B3 car it's most likely during the first two shifts rather than the midnight shift.
If all post assignment were filled and there was a surplus of officers we would have "umbrella cars". These officers would cover two or three post assignments to help the post officers. These would usually use the callsign 514, 515, 516, 517, etc., and the callsign would be assigned by the supervisor.
I'm not sure if they've changed some things as far as post assignments go. That was the way it was done when I was there.
The supervisors used a non-alphanumeric call, i.e., 510, 511, 512, 520, 521, 522, 530, 531, 532, etc. 510 was Shift 1's Lt., 511 and 512 were the Sergeants. 540 was the midnight Lt., 541, 542, and 543 were the Sergeants. If you hear units identified as "Western xxx" then these are the district detectives, district narcotics officers, and any other specialized units assigned to the district. Western 500 is the district Captain.
Hope this info helps 'ya and it was in current use when I worked for the county.
D. Lea, N3WKM
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