2 year bond with company and company changed policy

The company was offering two appraisals per year. Now they changed to one per year. There are two cycles, May and November. The employee who joined in December will not be eligible in may cycle. he will get the appraisal in Nov cycle. But now , My company changing it to April. So, technically , i will not get now in November cycle, I will have to wait for April. Is this violation of terms of condition by company and bond will be voided due to this. Here is company email. Dear All As we transition our organization into building the next Generation Product company, it is important we amend our processes which support it as well. As a first, we will now move towards an “Annual Compensation Appraisal Cycle” What does this mean: We will review our performance based on metrics laid down every quarter. However, the compensation change will happen for employees only once a year. Doing regular performance review help individuals get feedback, support learning and growth & avoid recency bias We will follow April to March cycle - Coming year, we will target to complete the appraisal process by April 30, 2017 Mid-year correction / promotions will happen only through Internal Job Posting. Detailed guidelines for this will be shared soon