I did a tour recently at the end of March, at the box office they had a schedule for the day's tour, so I guess it changes dependant on what will be available to view. They were still laying the new turf at the time we did the 100 + 200 levels, a couple of suites, the media centre (I still call it the press box), the away clubhouse, home dugout, we even went onto the field though they did say it was the first time this guide had been allowed to do that.
http://imageshack.com/a/img661/1750/Q5JUXt.jpg
http://imageshack.com/a/img908/338/vi35kN.jpg
http://imageshack.com/a/img538/7351/Gfc9lP.jpg
http://imageshack.com/a/img903/3598/rHbYj2.jpg