last night I spent 10 minutes on a post, and when I clicked submit, I
got a msg that the page had expired. How long do we have to write &
submit a post?

Write you posting in notepad or you favorite text editor and copy/paste into the forum editor.

Another thing you can do is copy the posting into the clipboard before you submit it, just in case. If the posting fails and the back button does not work, you can login again and paste the post again.

write faster..... I have not had that problem.... but if you are having it happen..... click the back page and maybe it's still there..... copy and paste works well....

when all else fails, use common sense. Copy & Paste...ok. Still, I'm curious if there is pre-set time out on the posting.

I've never noticed a time limit and I spend an obnoxiously long time typing up some of my diatribes. A time out message usually means the connection to the site was severed somehow. Either on their end or yours. Notepad and/or copying to the clipboard is usually wise for longer posts. I've lost quite a few posts on the tubes over the years and it's always annoying. Welcome to the forum.

BTW, on a post of a few minutes ago, I timed out again. This time I checked
for details of why it happened. the error msg was that cakewalk was no longer responding, and the reason given was ie 9 related: "AppHangB1"
whatever the hell that means.