If we are a second section of a train, then the train symbol will have a (2) in it, such as CBTSA(2)-28, Coal, Black Thunder-San Antonio, 2nd Section, of the 28th (day).
The “B” means a second schedule, i.e. 2 trains between the two points every day or at least on a regular basis. A second section is indicated by a numeral “2” in front of the symbol 2MWCRV-28
I share your missing the long train symbols. On the Southern Pacific a symbol would look something like 2LABRT3(K)07. The way it worked was 2=section, LA=Origan, BR=Destination, T=Descriptive Designation, 3=Route Code, (K)=Hazardous Materials and 07=Date.
In all honesty I miss Conrail’s nice simple system…told you what train it was what type and where it was going in a few simple letters. This garble CSX and NS have tell you nothing. Unless you just happen to know what train it is and its destination its all a guess.