Not a Sovereign 150, but I do have a Sweet Caporal 150 of White with a larger bottom border like the Sullivan shown.
Pat R has done some really heavy lifting on his various Piedmont 150 plate scratch threads, and on those threads he has fairly well established that the hypothetical T206 sheets for these involved vertical columns of the same subject.
Links to a couple of those threads:
https://www.net54baseball.com/showth...hlight=scratch
https://www.net54baseball.com/showth...hlight=scratch
It is a distinct possibility that Sovereign, as well as other brands, followed this sheet printing pattern, and thus each subject would theoretically have about 9% of its population with larger bottom borders. Of course that assumes that all sheets were uniformly cut, which is definitely not the case.
Brian