I'm not sure which of your posts I should reply to as they are both consisting of the same thread question.
But, FWIW, I have never really noticed the situation you describe, even if it does exist, but then again, I never have to log in and maybe that's because I don't log out, even when I go about visiting other websites.
Actually, whenever I come or come back to this site, I usually hit "Quick Links" and select "Todays Posts". That usually gets most messages arranged in the order I can deal with.
Sometimes, actually quite often, the arrangement doesn't always make sense from what the title says:
The threads below have not been updated since your last visit or since forums have been marked read.
Updated threads used to always show in bold, which is not always the case now, but it's been that way for some time now.
But why not just login and not bother logging out and then you should always be logged in when you get back to the site??? Works for me.