It’s a mission that activates after you play a battle. Play 5 more (with a tank over tier IV) and you get 6 Romanian flag decals. Thanks to David Blader for the extra screenshot.
Great initiative from Wargaming!
https://thearmoredpatrol.files.wordpress.com/2018/03/shot_015.jpg
https://thearmoredpatrol.files.wordpress.com/2018/03/shot_006.jpg
