No, it doesn't work like that. With music, things can change very suddenly and often a rehearsal gets rescheduled. The 24 hour rule has helped me many times, and sometimes anyway, when you book a ticket, you get a better idea in the 24 hours following the purchase. I tend to buy these tickets just after midnight, which gives me the maximum time because often the OTAs say you can only cancel within 24 hours on the same date as purchase.