.net - Do you need 2 instances of Azure websites for SLA like Web Roles?

Question

On cloud services web roles you must create at least 2 instances to get Azure's 99.95% SLA because when they do updates to the servers' OS etc, Azure will need to restart the machines (one at a time). This is well documented and you will be shouted at by the portal when running a one instance web role for doing this.

With Azure websites you don't get such warnings and I cannot find any documentation suggesting 2 instances for the 99.9% SLA. However, I also can't find any documentation saying that you don't need 2 instances for this SLA.

So which is it? Do I need 2 instances for Azure websites' SLA like web roles or is that a thing of the past?

Answer 1

A developer on the Azure Websites team has replied here that

the SLA for any Azure Website on the Basic or Standard tier is 99.95%

Just having one instance of the site is enough