An email from a Mozo representative to a customer indicates that the company has stopped making the colored plastic covers for Microsoft's Lumia phones. The email states Mozo will continue to make and sell the wood covers for those phones.
TheWindoze.fr has posted the contents of the email, with Mozo responding to a customer's inqiiring of getting one of the blue covers for his Lumia phone:
We have sold all the blue covers patch and are not going to produce any more of that color nor other colorful covers. Regarding the recent Microsoft news we decided to focus at the wooden line and other products like Surface sleeves etc.
At the moment, Mozo's online shop does show the blue covers for the Lumia 950 and Lumia 950 XL are now out of stock, and it sounds like it will stay that way. Other colors for those phones are still available, but if this email is accurate, they could soon sell out.