Due to policies we cannot control, the upstream only provides us with a /64 at this server, does not provide a higher subnet, and their routers do not allow subnetting on the /64. We have found an internal workaround for this issue using VirtFusion's IPv6 Route Blocks function, and are able to provide servers with a secondary network interface with a /126 (externally accessible like a /64). However, the separate network interface is on a different platform (MacVTap) and unfortunately can't be auto-provisioned, therefore requiring a one-off dedicated activation fee for the task.