Hi Vicenç, I plan to turn on the UploadCampaigns and CentralNotice banners sequentially, country by country, on September 1 00:00 local time -- and turn them off exactly after a month's time.
The first country to start the contest will be the Philippines (at 16:00 UTC on August 31), then India at 18:30 UTC, then Belarus, Kenya, Russia, Ukraine at 21:00 UTC, then the countries of the European Union and South Africa at 22:00 UTC, etc. The last country to join the contest will be Israel, on September 13 21:00 UTC, and ending on October 14 21:00 UTC (because they follow the Hebrew calendar).
I agree it will be most useful to have such a table, and will prepare one on Commons soon -- thanks for the idea, it's appreciated ;-))
And as for the category, it indeed should be empty -- please feel free to remove all images that are categorised into this category or one of its subcategories.