Is it necessary to repeat prayers performed while considering madhy (pre-seminal fluid) pure, after a change of opinion, and is it necessary to perform them in order?

According to the majority of scholars, madhiy (pre-seminal fluid) is impure. However, narrations have been reported from Imam Ahmad and some of his companions stating its purity, and some scholars consider it to be on the same level as maniy (seminal fluid). If you follow those who consider it pure, then you are not required to repeat the prayers. But if you revert to the view of the majority, that is the correct opinion.