The STS-135 launch with the orbiter Atlantis on July 8, 2011. The next launch from LC-39A could be the Falcon Heavy.
I wrote on May 19 that I'd had confirmation SpaceX was interested in Kennedy Space Center's Launch Complex 39A for the Falcon Heavy.
Space News reported today that their research indicates SpaceX was the only party to submit a bid to negotiate a takeover of the historic launch pad.
Space Exploration Technologies Corp. (SpaceX) appears to be the only company that put in a proposal to NASA to take over one of the space shuttle’s mothballed launch pads at the Kennedy Space Center (KSC) in Florida.
NASA declined to comment on how many bids it received in response to a solicitation that closed on July 5, but a survey of U.S. launch companies by SpaceNews shows only SpaceX saying it put in a proposal to take over Launch Complex 39A.