What I failed to understand from the datasheet is if this copper is for top layer or bottom layer or doesn't mind and can be used for both layers as well. It says "TOP VIEW", but I suppose that this stands for material view. This is important for me because it is going to be a single layer board and tny268 will be in through hole case.
Also the datasheet uses the term "Copper underneath the TinySwitch-II", avoiding to mention which layer would that be.
According to table 1 in page 1, both through hole and smd cases have the same output power, but I need to be sure about copper layer.