@fosdem I was asked privately for the "how", and figured a public reply makes sense
https://www.ripe.net/publications/docs/ripe-801 is the policy.
Fun fact: The extra time around an event used to be 1-2 weeks, and this was distilled pain as I had to chase #FOSDEM #BGP upstreams to update sessions, filters, etc and usually needed to escalate through to last level support
Before automation and the Cloud, a new #BGP announcement took days to weeks by default
So I got the #RIPE policy changed and extended to a month :)