Howard Stern’s contract with Sirius XM Radio expires on December 31, 2010, and after that Stern is a free agent. Stern has yet to announce his post-Sirius plans, or if he plans to stay with the radio channel under a new contract. Since he’s probably not replacing Simon Cowell on American Idol, Stern might even retire! “Howard has said that if he were to stay [with Sirius], he wants to negotiate a later start time for the show,†Pop Eater reports. “But Sirius execs aren’t too pleased about that idea.†Since Stern has already had an incredibly long and successful run, raking in another $70 million last year, some are wondering if his time is up, or if he’s just keeping his future plans under wraps: “While it may look like Stern’s staff has no idea what he is up to from the outside, this group is like a family and they have access to way more information than we know. But they’re loyal.†[Pop Eater]