No thanks to this forum for eating my post that I worked on for 20 minutes. I mean FT. Whatev yo.
I've had the forum black hole long posts too. Quite infuriating! It's just a guess, but there may be some sort of built in time out. Anyway, if you're working on a post for a while, copy the entire work in progress and save it off to a text editor for backup that way you don't have to start from scratch.
Or, if you know it will be a lengthy post don't do it from a phone and type it up in Notepad or something then paste it in when you are done. Sorry that happened. It's frustrating as hell. I know all too well.....