I appreciate what you guys are saying; but I see significant differences between your examples and "Unbroken". The main one being the fact that those songs weren't released as band singles. "Unbroken" was promoted, by Bon Jovi official (Twitter, YT), the streaming sites, and Amazon, as a single by Bon Jovi. I think the only place Jon was credited as the artist was in the credits of To Be of Service.
I don't recall Jon saying it was a side project or any question of it being included on the album; but maybe I missed it. (Kinda like I missed the teleprompters in the Billy Joel performance).
IIRC, the first specific statement Jon made about
any of the music on the new album was that "one of the songs is a PTSD song." In the "Unbroken" trailer, Jon did say that it was written for the film; but he also said "it will be featured on our forthcoming album
Bon Jovi: 2020."
So, yes, it was written for the documentary, and nobody ever said, specifically, that it was "the first single from our upcoming album." But it was clearly the first song from the album to be released as a single; and it was consistently given as an example of the content on the band's new 'socially conscious' album. So, aside from them choosing to call it that, it still doesn't make sense to me why another song will be considered the "first (or debut) single" from the album.
Not a big deal, anyway; it's just a riddle to me. Thanks for trying to clear it up.