Funny. When it comes to Subway, I'm a cut-endian! Also, if I cut my own sandwich, I start on the cut. There seems to be quite a variety of rules involved in where I take the first bite.
If I fold, I start on the fold, but only on the round end. Which makes me a Folded Round-Endian as well.
And I seem to be a Top-Uppian, too. If it's on a bun, I never hardly ever turn the bun top to the bottom before biting.