If it is all in one hunt, your PH will make the call. Usually they want to get the toughest animals out of the way first or at least attempt to get them out of the way as you may well encounter some of your other wish list animals as you are looking for buff.
You don't need to over think it. My first African animal was a buff.


I am continually astounded at how quickly people make up their minds on little evidence or none at all.
Jack O'Connor