Perhaps that's it, KWIL. It doesn't seem a very satisfactory explanation though since, other factors being equal, it requires making it a "special case". That is "include every issue from xxx date forward except #4158" …. pretty much guaranteeing that "where is it" queries will be raised (possibly multiple times). Not to mention that reprints from older issues give it an intrinsic interest for some people on that account alone.
Simpler to just include it if it's available, I would have thought. Especially as it contains something that I'm interested in looking at
…. or perhaps it's just an oversight.