Just because the Apostles came together on Sunday to break bread doesn't mean the worship day was changed to Sunday. That's as plain as I can make it. If God wrote it in the Commandments, how can you possibly think one verse changes everything? It doesn't matter what day of the week First Fruits landed on in the Gregorian calendar, it's always First Fruits on the Hebrew calendar. Jesus kept the Hebrew calendar.
It would be good if you read the Bible to see christians celebrating on Sunday