If it was October last year when she was bred then it may have been that she had just stopped ovulating, even though she was still willing to stand for the stud, or he may have hobbled her and she had no choice but to stand. Hopefully you’ll have better luck in April, but if you don’t then I’d definitely get JB to do the uterine infusions before I switched studs, especially if you really like the stud.
Hey - Good luck on your first day at work today!
Maybe with the time change... you’re already there?