The rage in this thread is kind of hilarious. Of course they were going to extend LOTB to three years, they more or less said so. There was never a guarantee that the album was even finished, let alone that they'd be ready to release it next year (or this year, as some fans speculated). It’s funny how deep speculation and reading between the lines goes on here but often the most obvious things are ignored. Hopefully this tour goes to Asia, Australia, and some of the territories they haven't hit yet.
I’ve noticed Maiden tend to change the setlist once they start repeating locations on a tour, so it doesn’t seem too implausible that we will see some changes. A new song wouldn't be entirely out of the question (perhaps replacing FTGGOG), but I doubt it. I could see them bringing in more classics, especially from the Di'Anno era. Next year marks 40 years since the debut. They're not typically an anniversary kind of band but it is pretty significant and the timing works out if they're doing a cabaret tour. I could see something like FTGGOG or Clansman being replaced by Phantom of the Opera, for example.
As far as the new album goes, I really don't think they're going to cannibalize their own marketing by co-opting this tour to promote a new album. They're going to milk this for all it's worth and then milk the next thing for all it's worth. That being said, it is surprising that they would tease new music and then hold off another year. At the same time, from the band's perspective, they probably recognize that most of the audience is more invested in Maiden as a touring act than a recording one. The album could be done but it is by no means a sure thing. I'd love to see it next fall, but I'll be happy to hear it whenever it comes out.