I have heard (in conversation) that there are early Torah scrolls, or sources mentioning this, that don't follow the two-column Haazinu that is now universally written; but rather, something similar to the Az Yashir 'brick like' structure.
Could someone locate this source please? If it is indeed the case, why was it different? Was it a legitimate way of writing the song? And is there a reason why it is no longer adopted?