You have between January 1st and February 14th to go back to original Medicare. This enrollment period is called ADP or Annual Disenrollment Period.
During these 6 weeks you can go back to original Medicare (1-800-633-4227) but you will have to pick up a Part D Prescription Drug Plan. If you are a Veteran and you go to the VA for your medicines, you will not have to. VA drug coverage is considered credible coverage.
I would assume that most people who go back original Medicare at this point will also enroll in a Medicare Supplement.
If you cancel your MA plan in January, you will be on original Medicare on February 1st.
If you cancel your MA plan between February 1st thru the 14th, you will be back on original Medicare on March 1st.
If you need help or have any further questions, please call or email me.
Regards,
“Medicare Dave” Silver