I've recently received sketches from Creekmud and Soot for the covers of book 4 (The Worlds of Long Division) and book 5 (Roy: Between Marco & Tracy), respectively.  They are looking fantastic and I am hopeful that both volumes can be sent off to the printer very soon.  Existing customers will get a notice via email as soon as they are available for purchase.

Thanks for your patience.

—Ursus