I am not one of the developers so I can't tell you why it is doing that. If you have a different browser try popping over into it and see if you get the same thing. If it were after 12 hours I could see it doing this, but I've not had what you are describing happen at this time.

I tend to bounce between Chrome and Firefox and you could see if it'll let you edit in one. (yes, you are a smart guy and very possibly already tried this)

Another thing that popped into me mind is if you are logged in using something other than the POSTING, or OWNER password/key... could that be a possibility?