Anytime they feel like biting they will. Anytime they don’t… you ain’t going to change their minds.
I honestly don’t think there is an hour on the clock I haven’t caught one.
If I looked at my numbers, it would be highest catch rate when I’m most likely to be fishing them.
I have a day job. I tend to fish sturgeon in the fall. Dark comes early in the fall… lot of big hour fish.
I’d say later in the year the more a day bite persists, but that’s actually wrong…it’s just that the waters are less busy later in the year allowing you to fish where you want.
I fish flatheads during the day too but quick research would tell you that to be wrong time to fish. Tell that to two of the 3 flats 50 lbs or over I’ve caught.
So yeah, go when you can and use shad