Yes, they should have a contingency plan to bring things onto another hosting provider within 1 or 2 days. Anything else is negligence from a business continuity perspective for a company that size.
Companies plan for utilities to go out, which don't even have competition. It's insane to operate just hoping Amazon doesn't get hacked, freeze your account, experience a catastrophic failure, or just decide to quadruple the price overnight.
If uptime has any relevance to your company at all, have (and test!) a process to move everything to another provider in a mostly automated fashion.
Companies plan for utilities to go out, which don't even have competition. It's insane to operate just hoping Amazon doesn't get hacked, freeze your account, experience a catastrophic failure, or just decide to quadruple the price overnight.
If uptime has any relevance to your company at all, have (and test!) a process to move everything to another provider in a mostly automated fashion.