Retroactive certification period for medically needy shall mean one, two, or three calendar months prior to the date of application. The retroactive certification period begins with the first month Medicaid-covered services were received and continues to the end of the month immediately prior to the month of application.
Retroactive certification period means three cal endar months prior to the date of application for applica tions filed on or after February 1, 1985, two calendar months for applications filed on or after January 1, 1985, and one calendar month for applications filed on or after December 1,1984.