How can I reboot an instance that is stuck "modifying"?

Summary:

I cannot stop/reboot or even send diagnostic reboot/interrupt. All actions result in "this instance is currently being modified, try again later"

Content (required):

After a recent infrastructure outage due to cooling issues in Ashburn, my instance will not respond to any actions, and says that it is currently being modified. The instance shows as "running" but is not accessible. This could be residual issues from yesterday, but 24 hours seems like a long recovery period (even for us free tier folks). I'm not sure if there's another way to force this instance to restart, or if I simply continue to wait.