According to Doll Chateau retailer Mint on Card, The company has decided to release Holiday event doll Ada as a limited edition doll.
From MoC:
Due to much demand from Doll Chateau fans, DC has decided to make Ada available for purchase for a limited time! She can be pre-order though us until February 27th. Ada can be found in the Doll Chateau ‘Pet Dolls’ section.
Ada will also be available from Doll Chateau and other authorized Doll Chateau retailers.