Bear, you should be able to get to a point to where it takes an absurd amount of arrows before your form starts breaking down and shot fatigue creeps in.
I'll be honest, after coming indoors for spot league in the winter after a long season of minimal shooting while hunting every chance I get, I admit that arrows 45 through 60 are a bit rough.
But with a solid form and shot sequence, you can muscle through those moments of fatigue and execute a good shot.
Right now at the peak of the IBO competition year and gearing up for hunting, I'm shooting roughly 100 arrows per day, and if it weren't for obligations around the house and family, I'd be shooting 150 to 200 if time permitted.
Focus on your form, bone-on-bone support in your bow arm, and good back tension, and you should be able to shoot way more than 4 good arrows per session.