IPv6 SWARM (to IPv4 containers)

We have an IPv4 application running inside docker containers. when used in IPv4 Swarm , everything Works fine .
one of our clients is Running IPv6 Hosts and we need to create a Swarm cluster with IPv6 addresses . (meaning also that all incoming traffic to our application is IPv6)
Question is : As we do not change anything is our application containers , does SWARM will know how to forward the incoming IPv6 Traffic and ‘convert’ it to IPv4 and vise versa .
IF not, What changes are needed to make it work ?

Thanks, Avi