I want to know the answer to the following question:
Who was the Holy Roman Church leader that authorized the change ?
All the background I'm provided with is that "On 4 September 1483, referring to the feast as that of "the Conception of Immaculate Mary ever Virgin", he condemned both those who called it mortally sinful and heretical to hold that the "glorious and immaculate mother of God was conceived without the stain of original sin" and those who called it mortally sinful and heretical to hold that "the glorious Virgin Mary was conceived with original sin", since, he said, "up to this time there has been no decision made by the Roman Church and the Apostolic See.". Is that enough to answer the question?