not yet >:(
i've had a look through the obvious files fsx.cfg most other cfg files and a quick look through the fsx folders and also used windows search. Didn't find anything. :(

There has to be a way to remove the timelimit quite easily (because M$ probably won't want to have to spend hours removing it) but it'll probably be hard for people like us to find.
edit: i cant even find the fsx.cfg now :-/