Every year, I watch as various companies sell leftover bare root fruit trees, shrubs, and perennials on deep clearance (often 50-75% off) late in May and in early June.
I have a 10 acre garden in Florida 15 miles north of Panama City, but live in Chicago.
Here is my experience;
3 years ago Home Depot was selling fruit trees for $10 on 4th July. I bought 15 and took them to FL in September and planted them, they all did well except a honey crisp that our yard man ran over with his lawnmower. Last 2 years Stark bros has been selling fruit trees for $18.16 each in May or June (there may be some pears left) and these I've potted up each year and taken them down in September to plant. The weather there is wet in the summer and dry in winter, so I don't like leaving them until November to plant. This year starks had them again, but we'd also already found $20 fruit trees at Menards. The Menards trees were potted but are not doing as well as the bareroot trees that I potted myself, 2 may not make it.
So for the questioner, yes, they can be purchased late, they come from cold storage so the buds are just opening when they arrive, but be careful to examine the trees from the big box stores to make sure they are really healthy. Also the stores like Home Depot do not take really good care of their plants, especially those in packets (berry plants etc.) and they are often already dead within a month of them arriving at the store. Your stores may take better care, but most in and around Chicago (Ace, HD, TCS, Lowes, Walmart) don't!