Let us keep it simple here. There is no such thing as a "double variation" since the green upper door is always one panel either side of the windows (either one panel left or right, clockwise or counter-clockwise, it's all the same).

With this in mind, then the placement of the green door in relation to the lower entrance door to the tower, is what constitutes whether or not there is a variation. If the green door is above panel #2 then this is normal. If the green door is anywhere else it is a variation.

As John mentioned earlier, there are seven possible variations. Simply the green door is in panel #1, #3, #4, #5, #6, #7 or #8.

Ron