Is there a maximum time lime for editing posts?
As far as I know, there is no maximum time limit other than "2147483647" -- this is what gets stored on my sandboxed server when I enter "999999999999999999999999999999" to that field.
I believe the default value on a fresh install is "16777000"
16777000 = Almost 32 years.
2147483647 = Almost 4,083 years.