OCP: 4.13.0
A cluster that was running for 51 days.
In the UI console:
Navigating to Observe
-> Dashboards
-> Dashboard "API Performance"
Apiserver "kube-apiserver"
Period "5m"

Time Range "Last 2 weeks"

Result:
"An error occurred
Gateway Time-out"

The above error is shown for:
1. API Request Duration by Verb - 99th Percentile
2. etcd Request Duration - 99th Percentile