We noticed that all of our instances -- in 3 different availability zones in US East -- all cycled at the same time. That was pretty disappointing. Kind of defeated the purpose of having things in different AZs.
> you may also want to take this opportunity to re-examine your AWS architecture to look for possible ways to make it even more fault-tolerant Basically they won't allow blame to be placed on them for anything they do. According to AWS, it's your fault this happened.
They set up the maintenance to have as little impact as possible by splitting availability zones onto separate days so that people utilizing multiple zones for high-availability would not lose multiple zones at once.
Afterwards, they gave a detailed breakdown, linking to the vulnerability and explaining both why they had to perform maintenance and why they could not share more details upfront.
They also provided information on how to improve the fault-tolerance of your systems so that future issues like this won't stop your workflow.
Amazon isn't placing "fault" on users; they did a pretty stellar job of handling a nasty vulnerability and treating their users as well as possible.