You can get many of the benefits by adding v6 and then ignoring the v4 for some things. For example, sometimes you might need to allow an inbound connection on

You can get many of the benefits by adding v6 and then ignoring the v4 for some things. For example, sometimes you might need to allow an inbound connection on v4, but if all potential clients have v6 then you can just ignore v4 for that server. It's not necessary to remove v4 immediately, although v6 provides ways to help do that when you want to. When you run dual stack, the v4 is there as backwards compatibility. It's lovely that people will simultaneously complain that v6 doesn't have backwards compatibility, _and_ also use the backwards compatibility it does have as a reason to not deploy it...