The patch comes on December 12 on the RU server (night from 11 to 12), meaning we should expect a December 13 release date on EU/NA. ASIA is estimated to get it a week later based on previous patch releases.
Reminder: if you have not recruited the female crew member from the Personal Mission compensation yet, do so before the patch; FV217 Badger will replace the FV215b (183), so finish the grind and have the tank in order to recieve the FV215b (183) as a special tank.