The calendar features a person waving the International Cooperative Alliance flag. In their right hand, they are holding a piece of paper that says "COOP". The rainbow flag was adopted by the ICA in 1925. According to Wikipedia, it symbolizes unity in diversity and the power of light, enlightenment, and progress.

Below the year, it says "ONE FOR ALL AND ALL FOR ONE".

I saw the image from twitter user sovietvisuals (nitter link)

Интересно ми е, какво означава България за вас? Гордеете ли се, че сте българи? Ако имахте възможността, бихте ли променили нещо?

From what i have read, the winning logos are not guaranteed to be chosen, so we will have to wait for an official announcement. I think there is a meeting today, so I would keep an eye on the official wiki and news pages. On the meeting on tuesday (12.12), the competition results have been discussed but I don't know what's been said.

Notes for the meeting on 12.12

Notes for the meeting on 14.12