Unless something is contractual and legally binding, I don't know why anybody would take a word of PR at any value. An SLA of 99.99% uptime, sure, I can probably assume there's organization incentive to uphold it, and even still, you should perform your due diligence. Some company like Facebook saying one thing and doing another is to be expected, especially when the stated reason is purely emotional and stands at odds with core business directives.