What is the UAT Environment SLA?

There should be no expectations on the UAT Environment.

Running Performance Test?

You can not run a Performance Test in the UAT Environment. The UAT Environment is a very small fraction of the Production Environment. It would be a waste of everyone's resources to do a Preformance Test using the UAT Environment.

What happens if someone decides to run a Performance Test?

Your IPs will be put on the blocklist.