Heavy S3 load caused image processing time to rise from the usual 150ms to 250ms at 15.19hrs UTC. Some requests took up to 20 seconds and 1 in 1,200 requests were rejected. It exposed a weakness in the Sirv Magento 2 extension, which incorrectly handled S3 warning messages, preventing images for certain Magento extension versions from loading. The S3 load issue was rapidly identified and resolved by 15.54hrs UTC. The extension weakness has been resolved by the release of a new Magento extension.