What are all the letters for a manifest supposed to be like U-LAUMQA1-08A (Laurel, Montana to Minnequa, Colorado)? I've never understood any of those ever
This is an educated guess, but most railroads have a symbol that they use internally for marketing purposes to describe the purpose of the train, it's origin, it's destination, and the date it operated. Someone from the BNSF may be able to identify the codes in the first position (U), i'm sure there are several, for unit grain, intermodal, unit coal, unit auto, &c. the next set of letters is the origin and destination, as you mention Laurel MT and Minnequa, CO, respectively. The third set is the date (ran on the 8th of some month); the meaning of the A is less clear; it might mean a train which operates on a regular basis, it might mean the first train of that particular date on that particular day.
Added at 0900 UTC:
Subsequent to writing the above, I used the parameters "BNSF train symbol meanings", and came up with this file
http://www.utu426.org/pdf/BNSF Train Symbols.pdf which lays out the various parts and what they mean. Note that at the top of the first page, the vertical pipe characters are intended to line up below the carets (upside down "v"'s). From this document, one can determine that U-LASMQA1-08A is the first section of an "unspecified unit train", originating at Laurel Montana, destined to Minnequa, CO, on the 8th of some month. The document does not clarify the meaning of the "A" at the end.
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