I do agree with you, sir. People at the time does not track 24 hour day. Besides, this verse proves that it was a Friday.
"Then he took it down, wrapped it in linen cloth and placed it in a tomb cut in the rock, one in which no one had yet been laid. It was Preparation Day, and the Sabbath was about to begin."
Luke 23:53-54 NIV
https://bible.com/bible/111/luk.23.53-54.NIV
I think this is why some people argued that he actually rose on a Monday.
One thing to consider in that conclusion and using that verse is that the first day after Passover is when the Feast of Unleaven Bread begins. The first day is a special sabbath. Any day of the week following the Passover in any given year would have been a sabbath. If Jesus was crucified on Thursday, then Friday and Saturday would have both been sabbaths that week.
Haven't they celebrated the Passover the day before Jesus was crusified?