(a) The amendments to Part 415 are effective immediately; provided, however, that a social services district has the option, with regard to existing child care services recipients only, to implement the provisions in section 415.1(g) of this Part regarding the definition of child care services unit and/or section 415.5(c) of this Part regarding the pursuit of child support as follows:

(b) The social services district must indicate which option it chooses in its consolidated services plan or integrated county plan.