Thanks for the connection. I found out that there is no way to globally delete Flags/Labels. I guess that if you are a real guru you could literally go into the files themselves and do the changing, but that's way beyond me.
As for Flag A, I guess I must have included these same individuals in the search for individuals that I assigned the second Flag (D) and Label to, and apparently overwrote the Label assigned originally to the first group (Flag A). That is apparntly causing Flag A to show as not available but only one Label appearing in the Search for Flags window. Again, you'd have to a real guru to go in and correct this.