I actually looked at the two times you're referring...

I actually looked at the two times you're referring to

17/09/01
17/09/08

and now 13/10/23

Here's what I found

In '01 SPX tanked from that session and wiped around 13.5% over the next week.
It then ripped up for the next few months, then onto a distribution phase for a few months then went on to wipe out around 35% in the next few quarters.

In '08 SPX tanked in that session, wiping around 4% that day.
The next two days had a 4% gain each day.
Directly after the second green day the index wiped out around 47% over the next few quarters.

Can we take anything from these precedents?
I think the one thing we can expect is volatility - so I'm happy I'm already in VIX calls.

Directionally I don't think it'll be straight forward (hence the volatility) but if history repeats then bears may have the edge but it'll likely take a lot longer to play out than most bears are ready for.

I've attached a couple of screenshots from the iPad - they usually come out pretty blurry on HC but Macs are busy rn so hopefully you guys can make out charts provided...
.