Most growers (commercial and home) don't spray plums and peaches much after harvest. Most of the sprays are targeted to protect the fruit.

In the past I've always discontinued sprays after harvest. This year I may spray peaches once or twice after harvest to slow down shoot damage of Oriental Fruit moth.

Peach leaf curl needs a dormant spray, but beyond that you probably don't need any sprays after harvest.

Peach leaf curl and possibly a trunk spray for borers.

Thanks I looked at Ga extention service peach and plum bulliten and it says the same thing you guys say THANKS Bill
PS always get good advice on GARDEN WEBB