To clarify Coots post further a C/O deviation ticket can almost always be slide forward or back a month.

So to expand on my perfect answer in post number 2: Yes C/O double deadhead banks are always split between the old and the new month. C/O deviation tickets (expenses) can always be slide into the other month (as long as it is within 3 days of the beginning or end of the trip).

Believe it or not the help file in the FOX system FAQs explains this very well.