They do alter the wording periodically. You see, they "adjust" the beliefs of the members. The "adjustment" usually comes in the form of a washtowel study article. Shortly after, they put out a new batch of books with the "new" wording--while telling people that their existing copies are out of date. They are supposed to then get new copies, with the "corrected" wording, and ditch their existing copies. That way, everyone thinks it has always been that way.
What they don't realize is that many people hold on to their old copies, compare the "truth" in the old copy with the "truth" of the new copy, and sometimes even hang onto the first batch until the third or fourth "correction" comes along. They do that so people can believe that it always has been that way, but the Filthful and Disgraceful Slavebugger fails to realize that there are a good many packrats (who hang onto everything that ever came from the Filthful and Disgraceful Slavebugger as treasure never to be destroyed) in the congregations. And, by comparing these originals with the "revisions", many have come to see the religion as bogus.
It's not just the Creation and Revelation book that has this issue. The Washtowels are altered--there are plenty of cases where the reprints and bound volumes differ from the originals. The Suffer Forever book had at least one "adjustment" (about Sodom). Even the Not Well Translated Bible is not immune to "revisions".