Doubt regarding the ncl-obc certificate validity.

To the respected dignitaries, I have a doubt about the OBC(Non Creamy Layer) certificate and income criteria. My father is an Circle Inspector (CI) in Andhra Pradesh Police department, which is a Group B post in our state. And we belong to a caste that comes under OBC in the center OBC list and we have a verified caste certificate for the same too. my father's income have just crossed above 8 lacs income limit (excluding agri and salary income) in the recent years. but in the last financial year, my fathers income was less than 8 lacs limit mark, and showing it we even got a NCL-OBC certificate a few months ago for our regional Tahsildar and a certificate issued by the same authority under Govt of A.P. It is said that, a candidate will be falling under creamy layer category in OBC, "if candidate's parents income is above 8 lacks for all the last 3 consecutive years". And i have also read in many sources that " even if the parents income is less than 8 lacks for atleast one year in last 3 consecutive years, the candidate will be getting NCL-OBC status" , perhaps through which even i got the NCL-OBC certificate form out state department. But I have been reading hear and there that, the income of the parents should be less than 8 lacks limit for all last 3 consecutive years, not just for 1 year among them. please clarify me this doubt, that the way and the provision through which even my state govt gave me the certificate is valid or not. and will my certificate be valid, for applying for any center level govt jobs like UPSC and availing the reservations? will they verify and consider my certificate as invalid by checking all last 3 years I.T returns of my father and mother? please help me with a detailed answer. Thankyou.