Ditto Southwinds comments. Bow hunted my Kansas home state for over 30 years and I would agree that his time frame is spot on. As anything else it can vary a little depending on the elements but hard to go wrong during that time. Happy hunting! :-)
I've used a Primos bow sling the last couple elk seasons and have found it to be very comfortable and easy to use both putting on and taking off. Fits my Hoyt perfectly! Have to admit though, its the only one I've tried to date.