Preventing 503 when applying VirtualService

Hi folks,

The page below indicates that we should wait a few seconds after applying DestinationRule before applying VirtualService. From my local testing, it seems pretty quick… just a couple of secs or so. But I don’t know how long it would normally take once this is out in production. What would you say is a reasonable number to work with for every, say, 1000 sidecars?