How Long Does A Navicular Bone Fracture Take To Heal?

I am 53 years old, 5'7'' 175 lbs. typically active and healthy. I cracked the navicular bone in my foot 8 weeks ago. I was in a cast for 4 weeks. I have been walking in an air boot for 6 of the 8 weeks. I was told to take the boot off; which I did for a week. The foot is very swollen, red and I am now back in the air boot. I have a very high arch. How long should it take to heal and will the high arch prolong the healing process?