An individual or couple is eligible each month beginning January 1974 for a State supplement under this chapter if the individual or couple: Is a resident of the State; Meets the SSI definition of aged, blind, or disabled in that month; Is a recipient of cash grants under the programs in the State's plan approved under Title I, X, XIV, or XVI of the Social Security Act in December 1973, or who applied for this assistance in the State in December 1973 and was subsequently determined to be eligible for a cash grant for the month of December 1973 under these programs; and Has December 1973 income as defined in Regulation .02B(1) of this chapter exceeding the amount of the individual's or couple's Title XVI benefit plus any other income as defined in Regulation .02B(2) of this regulation.