I do not have any personal experience with Bystolic, but I do take
Metoprolol, another BB. I have gone up/down on dose with my doctor's approval, from 50 mg a day to 100 mg twice a day, in an effort to bring a high HR down. It also brought my normal blood pressure down, and down too low. I'm now again on 50 mg, once a day and the HR is acceptable.