definately older than a year, you probably have at least a 3 year old.

Its hard to really put a determined cycle on a snakes shed, they shed really at random times.

I always suggest that people dont spray their tanks as it can contribute to scale rot, making a moist hide will help you with your humidity issues and allow the snake to access it if it feels it needs to. Also just try and keep your humidiy levels around 55-60 and up it when he is about to go into shed to about 70.

And for the scale rot i would go see a vet so that they can get you something to help.