A few days ago, I got a great email from Vellum. They wrote to let users know that if you use Scrivener as well, the new version 3.0 now has a choice to compile/export for "Vellum Export." That means when you use that option, Scrivener will create the docx file that Vellum requires in order to create your ebook.
Hurray! It's perhaps a small step that you now don't have to do, but it's one I'm glad to cross off my formatting checklist!
If you use Scrivener for Windows, ignore this update. Vellum doesn't have a Windows version at this time, so you can't use it anyway. But if you can get access to a Mac computer, even occasionally, check out Vellum for creating ebooks, and now print books. You can download the software for free to try it out. Pay only if you decide you want to create the files. I love Vellum! It saves me hours for every book I publish.
As a side note, I remembered as I was finishing up that I heard this week that Hallmark has an arm now called Hallmark Publishing. (I don't know when it started.) They are having an open submission period until September 3, 2018, for sweet romances and cozy mysteries. Check out their guidelines here. They also will let you know about future open submission periods via Twitter at @HallmarkPublish. Good luck!