"And no I don't agree that the Sabbath changed to Sunday. That's a false teaching that's caused all kinds of confusion."
It literally happend in history 300 years after jesus
323 Pope Sylvester I in his calendar give to sunday, first day of the week, name Lord´s day and give commandment to churchmembers to keep it as a holy day and so he change old christian and jewish sabbath to sunday.[8]
Mark 7:8
For laying aside the commandment of God, ye hold the tradition of men, as the washing of pots and cups: and many other such like things ye do.