I believe that when you declare/survey a road as part of a subdivision of land you automatically cede said road to GoB.

An exception would be a subdivision established as a stock situation whereby there were no separate titles and the "road" was an internal agreement by owners. I don't know of any such land subdivisions on island.

Am told it is no longer legal to have/create lots that do not have access to a roadway that somehow connects to the eventual trunk road. There will be some interesting discussions about this very point when the trunk road reaches a couple of older subdivisions that oriented all access to the sea.