At some point along the way, that setting was changed in the site software. People used to be able to edit their posts for a much longer period of time. I can't remember exactly why it was changed, although I think it may have been a result of some people who had a habit of saying bad things and then trying to cover their tracks.
MEC407
Moderator:
Pan Am Railways — Boston & Maine/Maine Central — Delaware & Hudson
Central Maine & Quebec/Montreal, Maine & Atlantic/Bangor & Aroostook
Providence & Worcester — New England — GE Locomotives