On December 1, 2015 the Subcommittee on Strategic Forces of the U.S. House Armed Services Committee held a hearing on "Russian Arms Control Cheating: Violation of the INF Treaty and the Administration's Responses One Year Later". Rose Gottemoeller and Brian McKeon were invited to testify, just as they were a year ago. There was nothing particularly new there, at least not in the open session, but a few details are worth mentioning.
As I understand what Rose Gottemoeller said, before that time the missile was tested in treaty-compliant manner, either from a fixed launcher or from sea (or maybe from an aircraft). Which definitely makes sense if this is essentially the same missile. (In all likelihood, this is the missile that was used against Syria in October - Kalibr-NK.) Then, in 2011, Russia probably tested it from a mobile launcher, which immediately made it non-compliant with the treaty.