"Come" as a preposition?

This is what I found in an article at Slashgear.com

>Springpad, the online and app-based platform for saving and sharing web content,
>managing notes and collaborating on projects with others, has announced that it'll be shutting up shop COME June 25th.
>Despite ongoing development of the service, it's evidently struggled to compete with the likes of Evernote and others,
>despite attracting over 5 million users during its six-year lifespan. COME the tail end of June, you'll need to find a new home
>for anything that lives on Springpad, and the company's said it's working on an export tool that'll allow you to save your data
>and/or move it elsewhere.

Here, "come" means "by / on"?? Intrigued, I checked at an online dictionary site, but it didn't seem to list this particular use...