[ceejayoz]

Their SLA guarantees 99.9% on a monthly basis. The 99.99% mentioned on the product page isn't guaranteed at all.

As for what happened, my money is on this: https://aws.amazon.com/about-aws/whats-new/2015/08/amazon-s3...

> You can now increase your Amazon S3 bucket limit per AWS account... Amazon S3 now supports read-after-write consistency for new objects added to Amazon S3 in US Standard region.

The 100 bucket limit used to be an absolute, unchangeable hard limit - rare for AWS and thus likely something deep in the architecture from S3 being one of their first services - so I suspect the lifting of that limit involved some fairly major changes to the backend.

[StabbyCutyou]

They actually would let you increase that, but only up to a certain point and only if you specifically requested it. I don't see them mention the absolute ceiling being lifted, so that is probably still in place somewhere.

I'd wager it's more likely that read-after-write change.