BGP Listen Port

Hello, From BIRD 2.0.0 I can see that the "listen bgp" command has been replaced with "strict bind". However this means that BIRD can no longer listen on a specific port. This is something I am using with 1.6.3 to operate separate BGP instances. For example on a server with a main instance I can test on a different port or on a switch where I don't want to replace the vendor's instance. Is this something that will return? Or have I missed something painfully obvious? Regards, Joshua