I know that Bradbury has been having a hard time, health wise for a while. His signature page counts with most of the houses that publish him regularly (PS, SubPress, Gauntlet) have trending downward for a while.
I would not be surprised if Easton has been holding on to those signature pages for a long time. I was in touch with EP customer service about a couple of other author signed books they published, in some cases years after the author has passed on. For authors they plan to work with more than once, they generally have them sign literally thousands of signature sheets. If you look at the limitation page for
Fahrenheit (below), it mentions the book title nowhere on the page. Even the limitation itself, pre-printed on the bottom, could have been added at a later date given the crappy generic font differences.
I wish Mr. Bradbury the best of health for years to come, however. On any given day you ask me (depending on what I have been reading that month) he is more likely than not, my second favorite author after King. Always in my top 5.
I would love to read more tales from him!