Can I change my mind later?

Yes — Medicare gives you regular chances to change course.

• Annual Election Period (AEP), Oct 15 – Dec 7: Join, switch, or drop an MA plan. Changes take effect Jan 1.
• MA Open Enrollment Period (OEP), Jan 1 – Mar 31: If you're already in an MA plan, you get one chance to switch to a different MA plan or go back to Original Medicare.
• Special Enrollment Periods (SEPs): Triggered by life events — moving out of a plan's service area, losing coverage, qualifying for Extra Help, etc.

Returning to Original Medicare + TFL is always allowed. Your TFL coverage stays intact regardless of which window you use.

One caveat for those considering a Medigap plan (uncommon for TFL beneficiaries since TFL already wraps Medicare): Medigap doesn't have the same guaranteed-issue protections after the initial 6-month window. Most TFL beneficiaries don't need Medigap at all.