You get to choose a Medicare Advantage Plan if you want one. You chose another option if you don't. It is not open season; however, CMS has let Sound take over my husband's Medicare without his knowledge much less his consent and while he is in the hospital. The letter, addressed only to him, came to my house. He is in assisted living when not in the hospital or nursing home and doesn't even reside here. He only knows about this because someone was here that could read mail addressed to him.
I just got back from the hospital. I asked him if he had signed anything or agreed to anything with anyone since he went to the ER. He said no but someone named David came to his room a couple of days ago wanting him to consent to something. He said he didn't, but he doesn't always tell the truth if he thinks he made a mistake. (He is in no condition to even comprehend what is said to him right now much less agree to it.) I think it was probably not these Sound people, but it just shows the stalking that seems to go on among sicker Medicare patients. Even legitimate business should not be conducted with a bedridden sick person.
I am going to see if I can opt-out on his behalf. I hope it is not too late for this current emergency. When he is discharged it will be to a nursing home rehab facility. What you want to bet I get a delinquent bill from Sound at some future time due to problems with properly getting my bill processed through Medicare then GEHA.