In this situation, we compute your second-entitlement primary insurance amount by selecting the higher of the following:

(a) New primary insurance amount. The primary insurance amount computed as of the time of your second entitlement under any of the computation methods for which you qualify at the time of your second entitlement; or

(b) Previous primary insurance amount. The primary insurance amount to which you were entitled in the last month for which you were entitled to a disability insurance benefit.