I'm going to attempt to explain what I was thinking and trying to find out, I think Hlogic has answered my thoughts.
I own 6 northerns with an orangey color areola and 1 cherryhead with whitish color areola.
The 5 that the lady fetched to my house for me to look at all had whitish color areola. These were 3 northerns and 2 cherryheads.
Does this mean that all 3 cherryheads and the 3 northerns with whitish areola are from the same region of locality, and my 6 northerns are from a separate region of locality.
Is this a way if I wanted to, to keep a true blood line?
No, cherryheads are a southern clade, population, locality, subspecies or whatever the taxonomic gurus decide is the distinction (if, indeed, there is any). In each of the 'groups' of RF's, there are quite distant and different populations. Like any widely spread species which is geographically restricted, there will be differences. Areolar coloration, along with head, leg and plastral color and pattern will differ between those subpopulations. As an example, the pic below is a Colombian RF from a specific region - a subpopulation with substantially different coloration than others...


