Have You Ever Thought About Changing Your Medigap Plan via Your “TRIAL RIGHTS”?

[GailL1]

  It is possible to do, without underwriting, but it takes staying on top of it and making sure that the timing is perfect. And this may also involve managing your health care expenses for the time that one is under the MA plan.

Medicare.gov - Learn How Medigap Works  

from the link ~ 

Trial Rights:

• If you drop a Medigap policy to join a Medicare Advantage Plan for the first time, you’ll have a single 12-month period (your trial right period) to get your Medigap policy back if the same insurance company still sells it once you return to Original Medicare. If it isn't available, you can buy a Medigap policy you qualify for that's sold by an insurance company in your state (except for Plans M and N). You may also have an opportunity to enroll in a Medicare drug plan at this time.