Hey, Jim, I'm in SC also.
Fescue, if cut at the proper stage and dried properly, will make a great first dutting of hay. Depending on the rainfall, you should be able to cut it about the second week in June. As to getting 3 profitable cuttings, that depends on the rain, but generally there are only 2 good cuttings, with the second one of lower quality hay. If you cut it 3 times the second 2 will be short. Having other grass mixed in complicates the picture. Bahia grass grows back quickly, but does not yield much hay. Common Bermuda will easily make 2, maybe 3 good cuttings. Johnson makes good hay if it is cut before it seeds out. I seem to remember opinions against Johnson grass for horses, but years ago someone told me that the US Cavalry used to like Johnson grass hay.
There are about as many opinions on horse hay as there are horse owners. Grazing fescue is not supposed to be good for pregnant mares, there seems to be some dispute about fescue hay and pregnant mares. I'm not a horse owner so I'm not ready to debate the issue. I'll sell hay, not opinions, especially when I don't have an informed opinion.