What does happen when your publisher closes its imprint? Well, it happened to me. The imprint that published me is no longer viable. When I reached out to the main publisher, I determined they just didn't have time for me. So, I asked them if it would be preferable if the rights to A Girl's Guide to Time Travel reverted back to me. They agreed with an apology.
Now, I have a book - unpublished. And I'm fine with it. I received limited help from the imprint for marketing (or even feedback), so it won't be much different than being self published. I paid for my cover because of the extensive marketing material I possess. I am toying with the idea of an alternate cover to appeal to all genders. (My demigod looks absolutely wonderful - stomach flip, included, but he might put off the male reader.)
I'm in the process of formatting the manuscript (I didn't get that back from the publisher), and then I'll got it on Amazon. My sequel is there already because I knew the imprint wasn't going to survive, but I wanted to get the story out there.
So, there is life - even after your publisher gives you back your work. In my case, I was really lucky that the imprint was willing to work with me.