This is behaviour that has puzzled me mildly for many years, through many MEP versions, but I've finally got around to asking about it.
Quite frequently I find that the value displayed by a KF does not match its position on the timeline, as in this example of KFs on a title object::
Higher resolution: https://dl.dropboxusercontent.com/u/4019461/MEP-KF-Times-1.jpg
P.S. I have a vague recollection I asked this before, a few years ago, but if so I haven't found it.