Probition period & consequential benifts

According to Punjab & haryana high court judgement in my case . ""in view of above after declaring Respondent no-2 to be ineligible his appointment order to be set aside and petitioner being the most meritorious candidate in this selection is ordered to be appointed with effect from the date when respondent no-2was appointed with all consequential benefits"" so accordingly,I have joined on 5-10-2015,w.e.f 1-11-2013 for the post of AE (i.e date of joining of of respondent no-2),& my appointment letter clause no-2,say that you are on probation for 2 years w.e.f 1-11-2013, but now department(center govt university ) given me a letter on dated 17-11-2015 say that your probation period period is extended for another 1 year,because 27 days is to short to excess the conduct of employee. Sir,I want to know that legally they can extend my probation period,because it is 2 years start from 1-11-2013 .& they also not given me consequential benefits.or also advice me i can go for COP against the department .