Polycarp claimed to observe Passover (as the Lord's Supper) on the 14th of Nisan with the apostle John, who is alleged to be the author of the fourth canonical gospel:
In the mid–2nd century, the practice in Asia Minor was for the pre-Paschal fast to end and the feast to be held on the 14th day of Nisan, when the Barley was found ripe after the New Moon near the Jewish lunar month of Nisan (no matter the day of the week on which it occurred), the date on which the Passover sacrifice had been offered when the Second Temple stood, and "the day when the people put away the leaven". Those who observed this practice were called Quartodecimani, Latin for "fourteeners", because of holding their celebration on the 14th day of Nisan.
The practice had been followed by Polycarp, who was a disciple of John the Apostle and bishop of Smyrna (c. 69 – c. 155) - one of the seven churches of Asia, and by Melito of Sardis (d. c. 180). Irenaeus says that Polycarp visited Rome when Anicetus was its bishop (c. 68-153), and among the topics discussed was this divergence of custom, with Rome celebrating the Pasch always on Sunday. Irenaeus noted:
Neither could Anicetus persuade Polycarp not to observe what he had always observed with John the disciple of our Lord, and the other apostles with whom he had associated; neither could Polycarp persuade Anicetus to observe it, as he said that he ought to follow the customs of the presbyters that had preceded him. - Quartodecimanism (Wikipedia)
But that gospel specifically denies the institution of the Christian "take" on the Passover because Jesus dies before the Passover:
[Jhn 18:28 NLT] (28) Jesus' trial before Caiaphas ended in the early hours of the morning. Then he was taken to the headquarters of the Roman governor. His accusers didn't go inside because it would defile them, and they wouldn't be allowed to celebrate the Passover.
Regarding the chronology of Jesus, the Gospel of John (e.g., 19:14, 19:31, 19:42) implies that Nisan 14 was the day that Jesus was crucified in Jerusalem, while the Synoptic Gospels instead place the execution on the first day of Unleavened Bread (Matthew 26:17). - Quartodecimanism (Wikipedia)
Do we have on record any endorsement (or denial) by Polycarp of the validity of the fourth canonical gospel and its alleged provenance from John?
And what about the three letters of John and the Revelation? Did Polycarp ever indicate that they should be considered the authentic writings of the apostle John?