Can I Change My Medicare Advantage Plan After the Dec. 7th Deadline?

Hello Toni:

I recently attended a Medicare Advantage meeting because my Medicare Supplement Plan F is costing me $220 a month and was going to join. A friend introduced me to your articles explaining the different Parts and Plans of Medicare. Now I am having second thoughts.

My question is if I change to an Advantage plan and find out it’s not working for me.  1) Can I return to regular Medicare and apply for a new Medicare supplement? 2) Will I be able to enroll in a Medicare Part D plan…