Ably change history: Timeouts and High Latencies Across All Regions

Ably reported major timeouts and high latencies across all regions starting 2023-09-01 15:18 UTC. Computed duration was 0 min, although updates report disruption until 15:31 UTC. Initial reporting cited transient load causing resource starvation; the postmortem attributed the incident to a DDoS affecting a significant fraction of connections to primary and fallback endpoints.