Why? Exactly why would Jesus correct a whole culture's alleged mistake if the alleged mistake was insignificance?
Note, the text below, Jesus set an example of Sabbath keeping while He was on Earth.
Luke 4:16 "And he came to Nazareth, where he had been brought up. And as was his custom, he went to the synagogue on the Sabbath day, and he stood up to read."
John 15:10
"If ye keep my commandments, ye shall abide in my love; even as I have kept my Father's commandments, and abide in his love."
If the Jews of the 1st century had lost of time, Jesus would have corrected the error, because He would not let his chosen people be in ignorance. But, it was not necessary because they were keeping the right day. Jesus wasn't politically correct, and He often rebuked the Pharisees for their honor of tradition, so then if they were not keeping the Sabbath on the right, surely He would have at least informed the Apostles. But, frankly, since the time of Moses the Sabbath sequence of day was set, when Jesus gave the children of Israel Manna six days a week, but none on the 7th day for 40 years, and the Jews never lost sight of the sequence of day till the 1st century, and thereafter the Jews were more and more dispersed and kept it holy till now.
All quite irrelevant. None of the claims in the table help to solve the 48 hour 'Sabbath'.