A slightly adjusted rumor rumor schedule is listed out here, apparently from a conversation. This would still be very close to what we were hearing from previous rumor sources, perhaps with the addition of Dark Elves in November.
Please remember that these are rumors, and to always add salt
I don't usually know anything or hear anything, but yesterday I was talking to someone who works for GW and he confirmed, to the best of his knowledge, this schedule:
August: Lizardmen, but that's not all
September: Big Surprise!
October: Space Marines, more than you expect
November: Dark Elves, more surprises
January: Dwarfs, and yes, more surprises
I stopped there because all I am really interested in are Dwarfs. I asked if the Big Surprise was Blood Bowl but he wouldn't say. I asked if the small surprises were supplement codices for 40k and he just smirked. I then asked if WHFB was going to get supplemental army books and he said he hadn't heard, but wouldn't be surprised.
I know people say these guys don't know any more than we do, but there it is for what it's worth.
I am going to speculate from what he said that the schedule above would look somethig like this with codex supplements added in
August: Lizardmen, Farsight supplement
September: Blood Bowl?
October: Space Marines, White Scars Supplement (could a second supplement also be in the same month?)
November: Dark Elves and another supplement, probably Marines and probably Ultramarines
January: Dwarves, and no idea