Performance is degraded across the board. Here's some graphs of the Journal Entry page load time and saved search load times, where you can see the difference pretty starkly. Average server load time almost triples, and the standard deviation goes up by more than 18 times, meaning that there's a lot more times than before where it's taking waaaay longer than that average.

@eblackey so when we were "notified" that this was happening it just looked like the standard maintenance thing:

but upon digging in with support after I showed them all those logs and complained for days on end of these issues, they finally admitted what was actually going on:

Root cause determination is still being conducted as this is something that cannot be determined overnight. What we know so far is that, the customer was moved to an Autonomous Database as part of our efforts to adopt the security, reliability, performance, and recoverability benefits of Oracle Autonomous Database and improve NetSuite's operational efficiency at scale.

It CAN be determined overnight.

Those kind of routine scheduled changes have never given any of the accounts I've worked in issues in the 15 years I've been doing NetSuite stuff. Had to roll back a few silent hotfixes over the years, but always have been able to roll the version back while they fix the issue in a dire emergency.