Technically, you’re right, but do you doubt that the sabbath was observed on Saturday, or that Sunday was the first day of the week?
See comment 134.
It’s a battle of tradition or inherited lies vs scripture..
One wouldn’t even care about the subtle difference, but because the serpent is subtle, knowing the enemy is one way to overcome..
We are born to have to choose satans false premise/choices and argue from there.
A blessing comes when one no longer accepts the false premise or choice and chooses the scriptures.
And other parts of scriptures may open up eyes previously blinded.