2.   Do those Medicare beneficiaries who are automatically enrolled into a Part D plan have the opportunity to change plans after their enrollment takes effect?  
The population of beneficiaries whose enrollment is facilitated includes those in Medicare Savings Programs, beneficiaries receiving SSI-only (and not Medicaid), and those who applied and were determined eligible for the low-income subsidy. Those in Medicare Savings Programs may switch plans at any time, effective on the first day of the following month. The remaining population whose enrollment is facilitated have a Special Enrollment Period that begins the first day of enrollment and ends on the effective day of plan enrollment or the end of the calendar year. 

Reference Information 

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