Sure, you can do that. But whatever you do, do NOT join both ends of the same billet together. Unless you are really good at circular tiller. Then feel free.
Heck, I wrote this answer and don't even know what it means either.
Honestly, I have looked at some staves I have and in most cases I can argue for either end being the one from the base of the tree. I honestly don't believe it would matter, but some in here will take it as an article of faith that you must always orient the stave with the earth or magnetic poles, or geopolitical fundamentals. And everyone knows that the reason you hold your bow in your left hand is so that the bow leans to the political right.
Stopping here. Prolly facing censure from a Moderator in the near future as it is!