Come on guys, it's just common sense, Maisie is shooting GOT, we don't have to know her schedule to know she's going to be very busy, and since she's probably (don't have a genius to figure that one) in a lot of scenes with the other kids, then yes, it's going to be a major factor.
It's not as simple as "oh they delayed it 10 months, they must be revamping the film completely", those release dates are like real estate, set up years in advance, it's not as simple as saying "okay, movie's done now, let's pick a release date", you already have Deadpool 2 too, the summer is packed, October has Venom, November has Dark Phoenix, that + multiple other films. So yeah, the Feb 2019 spot now that it's vacant, makes the most sense, and yeah it looks like a huge delay and it is but that's the nature of the business.
"Because it wasn't good enough", well, Sneider said it went well, just not great, ManaByte said on Resetera once again that one person told him it went well, the other that it was pretty awesome, that + one redditor who said he really liked it (if he did see it).
I lend more credibility to Jeff Sneider because he's top level in terms of source. It makes sense yes, that Fox would want the film to the best it can possibly be to make the most money, just smart business, I know some are having flashbacks of Fantastic4 or whatever but this imo a different situation and I have faith in this. And I also remember the rumors insisting that Wonder Woman was a mess, and bla bla, plenty of films get those kinds of rumors attached to them. Sometimes it's true, somewhat true, or other times, it's just ********
As long as they don't change Boone's vision too much but that it makes it perhaps better, then that's cool.