Yes, but there is no rush to migrate to the new edition - once stabilised the new features will continue to exist in nightly, in the same form as in stable.

And yes, presumably at some stage there will be a migration of the kernel from nightly to stable. There may be breaking changes. This will be a one time thing, and, (based on the current difference between nightly and stable and rate of change) not much more of a hurdle than changing C editions or gcc versions.

See my other comment.