Exeng, you raise two points:
Why is it that the 'last post' shown along each section (i.e. R & N or jet blast etc) does not correspond with reality. When you access that section that particular post can be a long way down the list
At the time you arrive at the home page, the Last Post entries are correct - for that specific instant that the page is assembled and passed to your browser. But the home page does not update itself automatically to your browser.
So once you have gone into a forum for a while and returned to the home page
using the Back button in your browser, the page is indeed out of date. This is because the cached copy of the page in your browser (which is what the Back button gives you)* is the same as it was when you entered the site, but in the interim, posts will have been made in the forums (perhaps many posts, at busy times) and the Last Post now appears further down the page when you now enter that forum.
If, on returning to the Home Page, you Reload (or F5), the page should refresh with the current view of the Last Posts.
in addition the time stamp on the 'last post can be many hours out of date.
I'm not sure if this is just an extension of the above, over a longer time interval, or if you have also observed the dreaded time stamp problem. There is a bug in many threads where the reported posting time is out by about 8 hours - it seems to be the difference between GMT and the server's local time (West Coast USA). This is only observed on the actual posts inside the thread - the date in the thread information in the forum is correct.
HTH
SD
*a simplification I know, and there are exceptions, but this is the general principle.