Hi Lee,
Apologies for the issue.
As you mention - it appears that the issue was due to a Redis failure - and some fail-over handling in our API Servers that didn't seem to work properly for all servers. This resulted in some RTT errors for some apps.
The issue has since been addressed (by rebooting the failing servers).
We're going to do a post-mortem on the Redis fail-over code to see if we can find the offending code-path - and we've added additional monitoring alerts that will look for just this sort of error in the future so that we can act upon it immediately.
Thanks for reporting it!
Paul.