This is for Kyfarmlife. I tried to leave you a comment, Rae, but I couldn't again, it may be a Firefox thing. But anyway, Georgia's udder doesn't look quite ready to me, in the picture that you posted. Mares are not as predictable as other animals. Before last year we were foaling out about 10 mares each spring. This year we only have two and then another in the fall. With the price of horses being what they are and the price of feed being what it is, we only bred two old mares that we would like to keep the bloodlines on.
We very rarely miss a foaling but we taste the milk, it goes from salty, to oily to sweet. When it turns sweet they will foal within 12 hours. I don't think that your mare will let you milk her, she sounds and looks like my TW mare. Is your mare gaited?
Here is a not-so-good picture of a waxed teat. The waxing will build up and get quite long but then fall off. Some mares never wax at all and one of our mares waxes for a full seven days before she foals.