Short answer: Original Medicare pays the hospice, not the Advantage plan; the person stays enrolled in the Advantage plan, which continues to provide any benefits that are not the hospice’s responsibility, such as extra benefits and Part D drugs unrelated to the terminal illness.
Under 42 CFR 422.320, while hospice is elected CMS stops most of its payment to the Advantage plan and pays the hospice directly through Original Medicare. Original Medicare also pays for other Medicare-covered services during that time, under the usual payment rules. The plan must tell members about hospice options in its area.
In practice: bills for hospice care go to Original Medicare, care for conditions unrelated to the terminal illness may be billed under Original Medicare rules, and the plan’s dental, vision or other supplemental benefits continue. Keep the Advantage plan card and the red-white-and-blue Medicare card handy.
This is the one big exception to the idea that an Advantage plan covers everything Original Medicare does.