I might do the same, depends if they have the same pre order deals as on the OP site.
What did you end up doing with your S21U? I held mine in my hand for 5 mins and knew I wasn't going to keep it, felt too much like a top heavy brick, awkward to hold so returned it couple days later.
Hopefully the OP9P will be more streamlined.
I had the S21U for a week, ended up sending back due to the cam being very average. It was a cumbersome beast and the final nail was the god awful bloat. The 8 Pro is much more comfortable to hold, better cams and much better software.
My 8 pro is destined for a family member. I've gone back to my Pixel 3 in the mean time. It's so tiny!
Amazon were pretty good at having the 8pro ready for launch day. Don't think they'll have any bundles but we'll see.
Camera wise the 8pro was already decent, this can only be better. Looking very forward to getting it.