1) The server users keep going above the user limit set by the admins.
Why can't those of us who have subscribed use a different "door" onto Pprune? I see that about 75% of those viewing most of the time are guests. I know it's not much, but I have paid, so why should I be bounced out?
2) To prevent spam from posters posting loads of junk all over the place, and advertising, etc.
See my answer above - not too difficult to remove the time limit for subscribers, surely?