Opened as 1 point favorite all over Vegas. Seriously, who do you bet with? How does he make any money? The line flipped to SF -1 at kick off. It never came close to the swing you describe. You either have a bookie who is truly a maverick, or ... well, I don't know what the or is.
I don't hold Grudges. It's counterproductive.
Here is your “Opening Line” on December 3rd.
https://billswire.usatoday.com/2020/...ancisco-49ers/