FYI something else that HAD been going on, found it annoying, but wasn't a big deal
When I work up the chain of posts from bottom to top, as I would get near the top of the list, obviously the most recent, the last few that were still indicated to be UNREAD by the icon in front of the post would DISAPPEAR. The number getting the icon cleared varied between 2 -3 each time.
Needless to say, there was no longer a way to jump to last post read, but I just popped in and went to the last page bottom etc
SO, the reason for this is to let you know that apparently that was ALSO part of the things a bit out of whack that you now have fixed
WOOHOOOO
Thanks again