Does anybody know why the collect for Commemoration Pope Telesphorus has been changed in 1962 or perhaps earlier missals from:
O God, who by the yearly solemnity of blessed Telesphorus, thy Martyr and Bishop, rejoicest the hearts of the faithful; mercifully grant that we who celebrate his martyrdom may enjoy his protection.
To:
Eternal Shepherd, regard graciously Thy flock, and keep it with an everlasting protection, by the intecession of Telesphorus thy Martyr and Sovereign Pontiff, whom Thou hast constitued Shepherd of the whole Church. Through our Lord Jesus Christ, Thy Son, Who with Thee liveth and reigneth in the unity of the Holy Ghost, God, world without end
It's because in 1942, the SRC issued the Common of One or Many Supreme Pontiffs. Prior to this, the collect for St Telesphorus was taken from the Common of a Martyr Bishop; the later one uses this new, separate common prayer for a Supreme Pontiff Martyr.