Most paid status monitoring services cover BGP route problems and ISP issues by only flagging an event if it's detected from X geographically diverse endpoints.
For the 30 seconds where you wait for failover to complete: that is a 30 second outage. It's not necessarily profitable to admit to it, but showing it as a 30 second outage would be accurate
TCP default is more than 30 seconds. The internet itself has about a 99.9% uptime. If one company showed every 30 second blip on their outage page all their competitors would have that screenshot on the first page of their pitch deck even if they also had the same issue. 2-5 minutes is reasonable for a public service to announce an outage.
Forgot about that centurylink BGP infinite loop route bug they had where it took down their whole system nationwide. A lot of monitoring services showed red even though it was one ISP that was done.
For the 30 seconds where you wait for failover to complete: that is a 30 second outage. It's not necessarily profitable to admit to it, but showing it as a 30 second outage would be accurate