Dear Prabhus, obeisances, all glories to Srila Prabhupada. In one essay [Thakur Bhaktivinode] Srila Bhaktisiddhanta says, "What are the shastras? They are nothing but the words of the devotees (pure devotees) or sadhus." Just like what is the law: it is nothing but the words of previous lawyers, and these lawyers (judges, high court, supreme court, etc) continue to make and amend the laws in the course of practicing law.
So Prabhupada made some amendment. What is wrong there?
Your humble servant,
Hansadutta
P.S. If Vyasadeva Maha Muni is still living on this planet, then everyone is a rittvik representative of him. Therefore his representative sits on THE VYASA SANA, the seat of Vyasadeva. Think about it. We don't say "Jayapataka asana" or "Hridayananda asana"; we say "Vyasasana".