Matthew Parris worries about what day Sunday is

There's a nice article in this week's Spectator about Sunday; Matthew Parris thinks he might have produced "the definitive analysis of the problem about Sundays":

The question that just won’t go away: is Sunday this week or next week?
Matthew Parris

So my editor was right. For the Creationist, Saturday being the Sabbath, the new week must start on Sunday. The Bible confirms this. Matthew xxviii 1: ‘In the end of the Sabbath, as it began to dawn toward the first day of the week, came Mary Magdalene and the other Mary to see the sepulchre.’ Dozens of New Testament references suggest the same convention. The early Palestinian Church followed it.

I'm not sure about "dozens"; nor am I sure about this:

So why did Christianity depart from the convention? Why did we not designate Saturday as our Day of Rest, and Friday and Saturday as our weekend?

As so often, St Paul seems to be the problem. In his arbitrary way, Paul started talking as though the Early Christian Holy Day had been switched from the Sabbath to the following day. He did not say why, but we can be pretty sure he was not relying on anything Christ said, or he would have cited Him. It is a fair assumption that Jesus, a good Jew, observed Saturday as His Holy Day. Paul was vague, however. The first text explicitly to mention Sunday worship is Justin’s First Apology, c. ad 150.

"As so often", Paul is cited as "the problem" without any corroborating evidence. Jesus is cited as "a good Jew" but Paul not. It's interesting just how easy it is in the journalistic world to blame Paul for everything. But then Parris also wants to "stop people with doctorates calling themselves doctors", so what would I know?