Is it possible that both prints were run at the same time, possibly from two different printers?
Do any other NSS posters exhibit the same "-X" traits, or is this the only one that has a number after the XX/XXX? If there are others, what has the consensus (or proof) been regarding those posters?
Are there any statistics to determine which poster is actually more rare/common? Maybe they started printing one, something happened, and they were forced to change the NSS information?
While I've seen a lot of conjecture about the order/history/etc. of the four different ANH poster versions, the vast majority of people seem to think that the 77/21-0 is the first. While my background in posters is limited, just thinking about it (the numbering in and of itself) logically makes me initially disagree with this being done on purpose.
From what I understand, the vast majority (if not all) of posters have the format of year/film syntax. Why would they have changed this, to add a "-0" to the first run of just this movie? And why would they have started with "0" as opposed to "1", which would have made more sense - if this was an official run. I could see the rationale if this was some type of printers proof or concept poster, but based on the volume in existence, and the fact that it was released to theaters, it doesn't seem to support that idea. If the 0 was meant to indicate a run, why didn't they increment it for future runs?
But, maybe they did only
intend to print a handful of them as a proof (such as this:
http://www.emovieposter.com/agallery/archiveitem/9568216.html ), with the "-0" to indicate it as a proof, and forgot to remove the "-0" before going into mass production? And partway through the production process, someone realized the "oops" and fixed it.
On the other side of the coin, the fact that the versions of the real printers proofs have the 77/21-0 seem to lend credibility to the theory that 77/21-0 is the first printing. I did a quick glance on EMP's auction history, and all of the printer proofs of Style A have the 77/21-0. Since the artwork is all the same in the different versions, I doubt they would have made more printers proofs for the subsequent versions (funky text, etc.). And on the same line of rationale, if the 'funky text' version was the first, why would it not be the one used on the printers proofs?
Lastly, the poster wasn't the only thing that had the "-0" appended to it. I've seen 8x10 stills that had it as well (which of course are being marketed as "the first run" of those items).
So, since the legit proofs have the 77/21-0 on them, I would put more credence into them being the first batch printed for distribution. I just have a hard time thinking that it was intentional.