It is really hard to tell if she will lay soon. Some females will eat all the way through the building process up until the ovy. Heck some claim their females eat even after they ovy. Some stop eating as soon as they start building.

Once you get a couple of seasons down you will have a good feel for the steps each of your females will take during the breeding season.

Have you tried to palpate her? Once the follicles get to about golf ball size you can literally see the lumps in her belly by holding her up and letting her body hang.