since shed periods are longer for larger snakes, and shorter for smaller snakes, I count down from the shed period.
I used to start checking for egg laying about day 25 after prelay shed, but have caught a female laying on 22 days after so I start peeking in on the females around day 20 after prelay shed now.
If I went by 45 days after that girls prelay I would have been 10 days late, lol.