Proof of Itinerary for 12 months?

Hi, I'm British and my partner is going to live and work in China for 12 months. I am planning to join him but am unable to go on a work visa so will hopefully be going on a multiple entry 12 month tourist visa. I'll have to leave China mainland every 90 days so when I'm first applying do I have to provide proof of every flight for the whole year? As I'm unsure where I will be visiting and what the plans are.