I genarally bring my snakes up from brumation in mid Feb. I try to get several meals into them prior to introductions of males which I usually start the first week or so of March. I tend to leave them together for a week or 10 days and then do a feeding followed by a rest for a few days to avoid regurge and begin the introduction of males again for several days, seperate for a day, feed and repeat this cycle until I see obvious copulations or signs of copulation and or evidence of females being gravid. The females may or may not go through a pre-ovulatory shed, but they generally always go through a pre-egg laying shed. Typically within 10 days of shedding they lay. I generally see the begining of this pre-egg laying shed in late April or early to mid May. it does vary from group to group. The jani, deppei and lineaticollis tend to go earlier, and the Santa Cruz island form (P.c.pumilus) typically don't lay until mid June.
Hope this helps.