ILR Qualifying period

Can some please confirm what is the correct qualifying period before we can apply for ILR? We came to the UK on 15 July 2011 so we are under the old rules.

I was under the impression that we could apply 28 days before the 2 years in the UK had finished so I had everything ready to send tomorrow (3rd July 2013) In the meantime the wife has been on ladyinter and she has been told by "many people" that we cant apply until September? (her visa expires 21st Sept 2013)

Im fairly sure I understood the rules but its not the first time Ive been wrong on something so Im just checking on here before I lose a grand by sending off too early.