I am not sure but I thought they made it randomly for players who can't survive such fights and still like to drive a tank.
If it would be on a regular saturday, they still would have a (small) chance to get the tank.
I think this is a good idea to put it back to the regular saturday, not because i don't like others to have the fluffy fluffy.
Just because it would be good for others to join those ( nice & chaotic) battles, gaining skills.( and have the tank afterall.)
Gotta work hard to reach something.
The last time I had the tank myself, it was unsprayable.
Keep fluffy unfixable, but make it just a lil stronger.
There are alot of ways to kill the tank, and its too easy to kill the tank, no real fun killing the tank....
They should make the tank that strong so that players would get a "Ending Boss Fight Game"Feeling.