Just got a reply –
They restored from a prev. working version to a new project and transferred that project to me.
I have to transfer domains over, but they credited me one month for a new plan on the new project.
EDIT
I had duplicated the project right before I hit the “break-everything-button”, but wanted to avoid the double-bill before I went-through with this course-of-action. Oh well.
Luckily our site isn’t publicly available yet, just deep-enough into the build to make a rebuild a non-option.
Once published, it will become SOP for our team to always duplicate before a restore, eat the bill, and have a working site while we work with support to get a billing credit.
I should also say that I asked if I can count on restoring from future backups on the new project. I was told that Webflow’s dev team team is working on it to make sure it doesn’t happen again.