I dont know a lot about these things, BUT when we drove past the site on Sunday (we live quite local) some of the marquees were up and others going up. I would hazard a guess that some of the other stuff was already onsite, so it does look like a really late decision.
HOWEVER, I am not surprised. There are SOOO many festivals this year, and the only thing that really set this apart from any of the others, IMO, was Bjork.
From all accounts, and the story locally is that once she pulled out, other acts / dj's started getting the jitters about cash, and one of the backers pulled out, fearing a large amount of refund requests and shortage of paying punters.
Still, bad news if you had bought a ticket...