Add a "Public - coming soon" option to access level for pages. Currently we use admin only when building pages or for pages that are only turned on for part of the year.

Additionally make it so any links to those while still in "Public - coming soon" showed a default coming soon page that could be configured rather than the default 404 page. This could work using the admin only option currently available as well but it makes it much more clear to distinguish between a true admin only page and a public page that just isn't ready to be viewed.
Thanks