WYSIWYG - glad it worked out for you. It's all kind of made up on the fly, unless you're a real band, and that's what rehearsals are for - to work out just how you're gonna do it every time.

You referenced the old time music on Honkingduck. My sense is that in the early days of recording the musicians adjusted their songs to "fit" the two or three minutes of recording time available, and that the record producer might be signaling them to extend or cut the song/tune. I wouldn't judge any of their patterns (AABB or AB, etc.) to be a standard - they might not do them the same way at all in a live performance.