That doesn't anywhere show Paul keeping the Sabbath, it shows him meeting with others to
teach on the Sabbath! Two different things! This is a straw man argument.

Paul says over and over again that he didn't keep the Law-- so that means he didn't keep the Sabbath!
Romans 1:10,
"I was in the Spirit on the Lords Day"
The
Apostle John celebrated on the Lord's Day (Sunday), not Saturday.
You asked to be corrected..
Romans 1:10 is "Making request, if by any means now at length I might have a prosperous journey by the will of God to come unto you."
I believe you are speaking of Revelation 1:10
Revelation 1:10 "I was in the Spirit on the Lord's day, and heard behind me a great voice, as of a trumpet,"(Rosh HaShannah)
Which is talking about.... The great day of the Lord...
it is a Festival Shabbat or Shabbaton
Revelation 4
Scene in Heaven
1After these things I looked, and behold, a door standing open in heaven, and the first voice which I had heard, like the sound of a trumpet (Rosh HaShannah)speaking with me, said, "Come up here, (Rosh HaShannah)and I will show you what must take place after these things." 2Immediately I was in the Spirit; and behold, a throne was standing in heaven, and One sitting on the throne.(Rosh HaShahhah)
Let me explain a little about (Rosh HaShannah) the Feast of Trumpets. It is known as the Days of Awe, they are the first feasts in the fall. The books of life are opened and the judge does sit down to look them over. Each judgment decree is announced with a trumpet.
Revelation 5
The Book with Seven Seals
1I saw in the right hand of Him who sat on the throne a book written inside and on the back, sealed up with seven seals.(Rosh HaShannah) 2And I saw a strong angel proclaiming with a loud voice, "Who is worthy to open the book and to break its seals?" 3And no one in heaven or on the earth or under the earth was able to open the book or to look into it. 4Then I began to weep greatly because no one was found worthy to open the book or to look into it;
5and one of the elders said to me, "Stop weeping; behold, the Lion that is from the tribe of Judah, the Root of David, has overcome so as to open the book and its seven seals."
6And I saw between the throne (with the four living creatures) and the elders a Lamb standing, as if slain, having seven horns and seven eyes, which are the seven Spirits of God, sent out into all the earth. 7And He came and took the book out of the right hand of Him who sat on the throne.(Rosh HaShannah) 8When He had taken the book, the four living creatures and the twenty-four elders fell down before the Lamb, each one holding a harp and golden bowls full of incense, which are the prayers of the saints. 9And they sang a new song(Rosh HaShanah), saying, "Worthy are You to take the book and to break its seals; for You were slain, and purchased for God with Your blood men from every tribe and tongue and people and nation. 10"You have made them to be a kingdom and priests to our God; and they will reign upon the earth."
The Day of the Lord is = to the days of Awe which we celebrate as the High Holy Days all of them and even into Sukkot.
John was in a vision of what will be in the end days in all its powerful scenes and incredible truths.