Sovereign 150 Series Question

[PolarBear]

I've been looking at the T206 Resource website and they say that there are exactly 150 subjects for the Sovereign 150 series. Looking at the Sovereign thread here, there are 151 subjects listed in the 150 series.

So, the first question is: Are there 150 or 151 Sovereign 150 subjects?

Also, T206 Resource makes an interesting claim that these 150 subjects are the original subjects of the 150 series before any additions and substitutions. They say that there are 159 total subjects in the 150 series when you count the additions (Wagner, Plank, etc.) and substitutions (Dahlen, Elberfield, etc.).

The 150 series is my favorite part of T206 and that was the first I've heard that it may be possible to determine what the original 150 subjects actually are.

So, my other questions are: What do the experts here believe about the original 150 subjects? Is it possible there really were exactly 150 in the beginning, or have there always been more than 150 from day 1?