Isn't it Interesting that the Gospel of Peter Seems to Place the Resurrection on the 21st of Nisan?

Now early on the Lord's day Mary Magdalene, a disciple (fem.) of the Lord-which, being afraid because of the Jews, for they were inflamed with anger, had not performed at the sepulchre of the Lord those things which women are accustomed to do unto them that die and are beloved of them-took with her the women her friends and came unto the tomb where he was laid. And they feared lest the Jews should see them, and said: Even if we were not able to weep and lament him on that day whereon he was crucified, yet let us now do so at his tomb. But who will roll away for us the stone also that is set upon the door of the tomb, that we may enter in and sit beside him and perform that which is due? for the stone was great, and we fear lest any man see us. And if we cannot do so, yet let us cast down at the door these things which we bring for a memorial of him, and we will weep and lament until we come unto our house.

And they went and found the sepulchre open : and they drew near and looked in there, and saw there a young man sitting in the midst of the sepulchre, of a fair countenance and clad in very bright raiment, which said unto them: Wherefore are ye come? whom seek ye? not him that was crucified? He is risen and is departed; but if ye believe it not, look in and see the place where he lay, that he is not here: for he is risen and is departed thither whence he was sent. Then the women were affrighted and fled.

Now it was the last day of unleavened bread, and many were coming forth of the city and returning unto their own homes because the feast was at an end. But we, the twelve disciples of the Lord, were weeping and were in sorrow, and each one being grieved for that which had befallen departed unto his own house. But I, Simon Peter, and Andrew my brother, took our nets and went unto the sea: and there was with us Levi the son of Alphaeus, whom the Lord ... (For Fragment II see Apocalypse of Peter.)

Could this then be the reason why the neaniskos is baptized 'after six days'? I don't know but it definitely shows that there were gospels which associated the Resurrection on a Sunday AT THE END OF THE FEAST OF UNLEAVENED BREAD ...