This looks like one their worst outage in 15 years and us-east-1 still shows as degraded but I had no outages, as dont use us-east-1. Are you seeing issues on other regions?
The closest to their identification of a root cause seems to be this one:
"Oct 20 8:43 AM PDT We have narrowed down the source of the network connectivity issues that impacted AWS Services. The root cause is an underlying internal subsystem responsible for monitoring the health of our network load balancers. We are throttling requests for new EC2 instance launches to aid recovery and actively working on mitigations."
I wonder how many people discovered their autoscaling settings went batshit when services went offline, either scaling way down or way up, or went metastable and started fishtailing.
https://health.aws.amazon.com/health/status?path=open-issues
The closest to their identification of a root cause seems to be this one:
"Oct 20 8:43 AM PDT We have narrowed down the source of the network connectivity issues that impacted AWS Services. The root cause is an underlying internal subsystem responsible for monitoring the health of our network load balancers. We are throttling requests for new EC2 instance launches to aid recovery and actively working on mitigations."