In the following interesting article (which, regardless of whether it is right or wrong, is nevertheless an interesting viewpoint, in the sense of iron sharpening iron), the author hypothesises that the Holy Day was never meant to be changed from Sabbath to Sunday.
In the course of the article, the author specifically addresses the phrase "first day of the week" occurring in Matthew 28:1, Mark 16:2, Mark 16:9, Luke 24:1, John 20:1 and John 20:19. The hypothesis of the author is that that phrase "first day of the week" in those verses is better translated as "one of the Sabbaths" or "First Sabbath". Given that there are seven weekly Sabbaths between Passover and Pentecost, the author further hypothesises that the phrase "First Sabbath" can be taken to refer to the first weekly Sabbath after the Passover high Sabbath.
What should one think of the above hypotheses?
possible on-topic re-focusing of the question:
Should the phrase "the first Day of the week" that appears in Matthew 28:1, Mark 16:2, Luke 24:1, John 20:1 and John 20:19 be better translated "one of the Sabbaths" - as suggested in this article in which the author hypothesises that "the Sabbaths" in question are the seven mentioned in Leviticus 23:15:
‘And you shall count for yourselves from the day after the Sabbath, from the day that you brought the sheaf of the wave offering: seven Sabbaths shall be completed. NKJV