If existing group disability coverage is replaced by a group certificate with a preexisting condition limitation and insuring 10 or more members, coverage in the replacement certificate applicable to the preexisting condition limitation for an individual who had been covered for that condition by the replaced coverage shall be not less than the lesser of the following: (a) The coverage of the replacement certificate without application of the preexisting condition limitation; (b) The benefits of the replaced group disability coverage until the individual’s preexisting condition limitation expires under the replacement certificate.