Pretty sure once an account gets invited it can post indefinitely.
Reason, I was in the open beta weekends and couldn´t access anything.
Then I enter my early access key and viola the account gets an invite and I´m happily posting. Even after early access was over and I waited 2 weeks to sub due to the ridiculously game breaking bugs.
No, I don´t think a sub only forum is needed. It would just become a boring kumbaya.
“I'm not going out of my way looking for devils;
but I wouldn't step out of my path to let one go by.”― Robert E. Howard
It is true, it's a hard line. But don't forget, there are many people who are playing, and may not re-sub after their first month, that may hate the game, the quests, the structure, the changes, or lack of. And often times the biggest trolls are first month players who didn't get the game they expected. In that case, I don't know what would help aside from a rating/flagging system on those posters. Either way, I'm totally fine with being locked out of the forums. But I'm also happy to be able to participate in them. Example, to get thoughts on mounts, getting opinions from more people is nice rather than less. So as has also stated, a general forums section would be appreciated that might have an open format. Or some kind of blocking system for people that are not abiding by forum policies. Either way, I'm looking forward to the console launch and subbing at that point, and greatly enjoyed the PC beta as well as watching the game while other play (or complain) at this point.