FYI, my view point came about beginning in 1969. Over the question of whether the crucifixion was Friday or Wednesday. Once from the New Testament Jewish calendar month day dates were deduced, it became a possible actual dates issue.
That is probably a big difference between how we arrived at our views.
When my father passed away I was given his copy of Josephus. He loved studying Scripture and history (growing up we had to stop at every single historical marker we passed).
So in addition to Scripture I had also grown fond of 1st century Jewish history, practices, and literature.
So by the time I started wondering about the day I already knew about the different Hebrew calendars, the different practices in regard to the Passover, and the divide between the Pharisees and Sadducees.
I knew some Jews began counting the day when they saw that moon (in the late afternoon) and others at sundown on the afternoon they saw the moon.
This is an issue when going through Scripture.
I knew one sect counted the day starting at twilight. If you see the moon and start 1 Nisan at that time then it would be earlier than if you waited until dark.
But I also knew another sect started tge day several hours later, after it had become dark.
These differences are minute - only a few hours, but they throw off each sects practices by about a day as both killed the Passover at twilight on 14 Nisan as they determined the date.