My experience has been that they "lock up" more at night. In that I put them together and don't see anything during the day but the next morning I see them locked up.

It's probably still early to see ovulation or much for signs but does depend on what shed in the cycle she's on.

I'm in the midwest and most all of my breeder females have shed recently or are in a shed currently over the past 2 weeks. I'm speculating that this is shed 2 of the 4 shed cycle but could be off (some females could be in #1). I'm starting to see a slight "glow" in some in their appearance but their behavior seems pretty normal otherwise.

Here is a good "how to" with pics of what to look for. Hope that helps!

http://www.ballpython.ca/gallery/breeding.html