[x] Allow prefix in our ACLs (`prefix-list wikimedia4`) - `198.35.26.0/23` already present (and used as `orlonger`)
[x] Create ARINs IRR DB objects (route & inetnum object for `198.35.26.0/24` and `198.35.27.0/24`)
[x] Create RPKI ROAs for `198.35.26.0/24` and `198.35.27.0/24`
[x] Confirm records are correct with http://irrexplorer.nlnog.net/search/AS14907 and Routinator
[] Wait at least 24h for providers to pickup new records
[] Depool ulsfo
[] Shrink ulsfo's `198.35.26.0/23` to `198.35.26.0/24` (`aggregate`, `bgp-out`, `pop4`) - https://gerrit.wikimedia.org/r/597486
[] Verify prefix is propagated properly ([[ https://stat.ripe.net/widget/looking-glass#w.resource=198.35.26.0/24 | looking glass ]])
[] Repool ulsfo
[] Delete ulsfo's `198.35.26.0/23` from ARIN IRR
[] Delete ulsfo's `198.35.26.0/23` RPKI ROA
[] Confirm records are correct with http://irrexplorer.nlnog.net/search/AS14907
[] Configure conditional aggregate advertising to peers of `198.35.27.0/24` ("only if one local contributing route" + `bgp-out`)
[] Configure router/server sessions (can be done out of order) - https://gerrit.wikimedia.org/r/597507
[] Add `198.35.27.27` to `border-in4 term authdns` (can be done out of order)
[] Verify prefix is propagated properly ([[ https://stat.ripe.net/widget/looking-glass#w.resource=198.35.27.0/24 | looking glass ]])