UnderlyingPaymentScheduleRateSourceGrp is a repeating component within the UnderlyingPaymentScheduleGrp component used to identify primary and secondary rate sources.
|  | 40705 | UnderlyingPaymentScheduleRateSource | Src |  | Required if NoUnderlyingPaymentScheduleRates(40704) > 0. | Added EP161 | 
|  | 40706 | UnderlyingPaymentScheduleRateSourceType | Typ |  | Required if NoUnderlyingPaymentScheduleRates(40704) > 0. | Added EP161
Updated EP169 | 
|  | 40707 | UnderlyingPaymentScheduleReferencePage | RefPg |  | Conditionally required when UnderlyingPaymentScheduleRateSource(40705) = 99 (Other). | Added EP161 |