Former “qualifying service”
6. Any period which any person was immediately before the commencement date entitled to count as qualifying service for any purpose (or would have been so entitled if he had been a member), shall, subject to the following provisions of this Part count as a period to which this Part applies for that purpose (or if he is not such a member, shall so count if he becomes a member in relation to it) and shall so count as a period of the same length as it then counted for that purpose.