Anyone trying to post a thread or reply over the last few hours will have noticed the 500 error when you come to send it. Every time it has happened to me, the post has actually been successfully posted but the error suggests it has not. I believe that is the cause of the recent spate of double posts because people are hitting Reply a second time when it is unnecessary.
Hopefully, Framework can correct the issue but I suggest people check whether a post has been successful before reposting. I am not being critical of anyone (it happened to me too) but just giving a headsup.