People affected by a Medicare Advantage plan cancellation who did not take action during the Open Enrollment Period can get a “special election period” (SEP) to make a move. This SEP runs from December 8th to the last day of February, 2015.
A person whose Medicare Advantage plan is being cancelled as of January 1, 2015 can enroll in another Medicare Advantage plan, or get a stand-alone Part D and a Medicare supplement.
See the post on “guaranteed issue”: https://medicareblog.org/medicare-supplement-guaranteed-issue/