When to count down after prelay shed?

do you start your countdown once you see her going into shed or after she sheds out?

After the shed

Yep, afterwards. Time frame can vary but usually within 3 to 4 weeks later she should lay. Good luck!

Once she has had her shed and the average is 27 to 35 days, it will depend on the animal and your temps. It can be much longer as well, in which case you need to monitor and decide whether it is normal or an egg bound animal.