Salary wise, it's a yearly salary pro-rated over the 7 months paid either fully for 7 months or split over 12 months, the choice remains with the employee.
1. Are you a full-time employee with all the protections that implies?
2. If you are not an employee how can what you do in your time off be controlled?
3. Are you guaranteed a recall, and what compensation do you get if not? Are you then made redundant?
4. What is the average annual flying hours productivity of full-time pilots? If you fly 100hr/m and no SBY's for 5 months you will produce at greater rate than 7/12th of an annual average. If you fly 75% of an annual average you could argue for 9/12 salary.
I had this at a young airline, non-union, where I worked 50% days for 50% pay, but produced 65% of average. No discussion. Long flights & no SBY's. Then came the union and 50% was limited to 450hr/yr.