Follow up from T122406 (and IRC chats)
cloud-instance-transport1-b-eqiad that connects the OpenStack instances to the Wikimedia infrastructure uses IPs in the 10/8 space, this should probably be renumbered to a public IP subnet (similar to any kind of customer interco link).
If I'm correct, we need 6 IPs in the subnet (cr1, cr2, cr1/2-vrrp, 2 hosts on the cloud side plus their VIP), so a /29 would works.
Longer down the road the prefix 185.15.56.0/25 should be advertised by BGP as well (currently the routers have a static route to 10.64.22.4), as well as possibly connect the cloud routers directly to cr1, cr2 (using 2*/31s).