Two is a rather small number of versions in which to find a West Gallery piece. Both compilers of printed collections and manuscript copyists frequently made alterations. These were often quite substantial, such as adding or omitting parts, or adding or omitting sections of music. West Gallery musicians find many of these revised versions of interest, and worthy of performance.
Where I have published a second version, it is because I came across it after finding the first, thought it worthy of publication, but saw no reason to delete the former version.