Full details in https://groups.google.com/a/wikimedia.org/g/ops-maintenance/c/1Un4cnLeXCs/m/5Txa5arzBwAJ
but the key points:
Equinix is expecting an increase in prefix announcements from AS15169 ... we would strongly recommend that you increase your prefix-limit to 15,000 for IPv4 by 22 December 2021 at 00:00hrs ... to avoid disruption to your BGP peering with our Route Servers
Primary RS: 27.111.228.122
Secondary RS: 27.111.228.123