I haven't logged on in a few years. Yet when I logged on today, my username was changed from yesir to r_yesir1 without any reason.
It's because of the nickname database update that allows players to 'book up' an already existing nickname. If the player whose nickname has been booked up won't appear in the game for a certain period of time, his nickname is passed to the one who reserved it. You can find more information here: http://en.tankiforum.com/index.php?showtopic=315003
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