Applying for tenured positions while on sabbatical I plan to apply for a tenured position at school B. 

I am currently on sabbatical at my school, school A, for the fall semester of 2015.  According to the rules of school A, I have to stay with school A for the whole year of 2016 (I heard that this is the case for most universities: you have to stay for at least six months or one year after you receive a sabbatical). 

Therefore, if I get an offer from school B, the earliest time I could start working would be the spring of 2017.  School B is hiring for the tenured position starting in September of 2016. And I am afraid that school B will not have openings in future after this hiring. 

So my question is: Should I apply to the position at school B and telling them: "I can only start working with you starting the spring of 2017"? Also, if I say this, will it affect my chance of getting the job? Or, would it be the case that I will not be considered and I should simply apply for academic jobs that advertise a start date of September of 2017?
Your sabbatical time may be able to be "bought out." 

If you leave your job after your sabbatical, the school may just want reimbursement for your salary. It is possible that the new school will be willing to pay that in order to hire you.

One case of this happening, I believe, was when Matt Welsh left Harvard after getting tenure (although he left for a company).