(a) A recipient may take an action, otherwise prohibited by § 42.710(a), that affects age groups differently, if such differentiation is based upon reasonable factors other than age.

(b) This exception does not apply to the use of an explicit age distinction, but to conduct that has the effect of differentiating among age groups. This exception applies when the factor (other than age) upon which the recipient's action is based bears a direct and substantial relationship to the normal operation of or achievement of a statutory objective of the program or activity.