MA Disenrollment Back to Original Medicare

Question for the brain trust here. I don't write any Medicare Advantage and am unclear about something. I have a client who was new to Medicare on December 1, 2016 so she is still in her Initial Enrollment window. She enrolled in a MA plan and now wants out. She called Medicare and Medicare told her that if he enrolls in a Part D plan she will be automatically disenrolled from the MA plan.

So, I ran the drug comparison for her on Medicare.gov and the recommended plan is with Humana...the same company she has her MA plan with. So if she does the enrollment right through the Medicare site, when

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