Updated August 12: DC have informed retailers that the final two issues of Bryan Hitch's "New 52" Justice League of America title, #11 and #12, are once again cancelled. This is what appears to be the final stop in a whirlwind for Hitch's JLA run, with these titles being part of a larger group that was solicited, delayed, cancelled in June, and by a report in July, uncancelled.
Back in early June, Hitch said that he has already finished writing and pencilling both JLA #11 and #12
No reason was given for second cancellation by DC.
Updated July 18, 2016 at 11:50 a.m. EST: After cancelling the final five issues of Bryan Hitch's "New 52" Justice League of America title, DC has again placed four of the remaining issues back on the schedule. The publisher has informed retailers that Justice League of America #9 is currently scheduled to arrive on August 10. Three more issues also appear in Diamond's system with new on-sale dates - #10 (August 24), #11 (September 14), and #12 (September 28). While the Justice League of America Annual #1 isn't listed in the Diamond's retailer database, it is listed on DC's own website for November 30.
This comes as the previously announced "Rebirth" Justice League of America remains absent from DC's schedule despite being originally pegged as a September 2016 debut.
Original Story: In a rare move by a Big Two publisher, DC Comics have cancelled the final five solicited issues of Bryan Hitch's "New 52" Justice League of America run. Justice League of America #9 through #12, plus Justice League of America Annual #1 have all been cancelled, but DC tells retailers they "will be resolicited at a later date."
This series has gone through several delays, with Justice League of America #9 originally solicited for March 30 but pushed back to, at last update, June 15. Issue #12 and the Annual were previously cancelled and resolicited last month for an August release - so this is he second cancellation for each.
When Hitch's Justice League of America issues do come out, it's one of DC's top sellers. In June 2015, the first issue was the fourth highest-selling book in the North American direct market, while March 2016's #8 was still a top-tier seller at a #34 rank.
Justice League of America writer/artist Bryan Hitch is, of course, the writer of the upcoming Rebirth Justice League relaunch, with the Rebirth one-shot and debut issue both solicited/scheduled for release in July.