According to the change comment, this edition has been set to 259 by a librarian, according to book-in-hand, in order to include the "about" section in accordance with GR page count policy (see here).
Excuse me, I wrote the wrong ISBN for the edition I had (didn't notice I was on a hardcover when I searched in WorldCat). I have the paperback edition, which has last text written on page 256 (the only other text after that is a publisher's ad).
ISBN 9781474600590.
This one is the one I meant to have changed to 256. My apologies.
http://www.worldcat.org/title/good-mo...