About 6 months
To be honest,a several weeks.Then I would move to aiming drills and then putting it together.
I made the switch 1 winter and practiced all winter in my garage on nothing but close range shooting.I did incoorporate some aiming into it but at really short distances.IMO,just too boring if all you are doing is shooting.MOSTLY blank bale though.I did continue to hunt with my wrist release but that was a completely different setup at the time.