The existing LDM-503 package has traces of a strategy to autogenerate substantial sections of the document from a milestone table maintained as the dmtestmilstones.csv file (as well as other portions from other .csv files). In particular, from this file a dmtestmilstones.tex file is generated, for use in schedtab.tex in Section 6 of the document, as well as a file testsections.tex used as the body of Section 7 of the document.
There are signs that both of those .tex files were hand-edited after the last time the autogeneration was performed, and these edits are at variance with each other, with the outcome that there are three versions, slightly differing, of the associated text.
The auto-generation script is not part of the Makefile, and its outputs are part of the Github acquis for the package, or this would have turned out differently.
Note also that the autogeneration script has a provision to substitute a longer description of a milestone into testsections.tex if one is available. Currently this is only the case for LDM-503-2, for which there is an LDM-503-2.tex file in the package (and a much more extensive f17_drp.tex file which it in turn includes). This longer description appears to predate the fuller, separate test specification for DRP and may be redundant or even in conflict with it; I have not checked that.