It will unlock the “11/11/11” bonus mission, which will give you 200 Tank Rewards points if you collect 10,000 XP over any number of battles.
Award period: until November 22, 2020, 06:00 CET (UTC + 1). This bonus mission, like all other Tank Rewards missions, will cease to be available on November 30, 2020, 06:00 CET (UTC + 1).
Many Thanks Seb!
doesnt work in asia