531. Any interested person, including the father or the mother, may, by any means, contest the filiation of a person whose possession of status is not consistent with his act of birth.
However, the presumed father may contest the filiation and disavow the child only within one year of the date on which the presumption of paternity takes effect, unless he is unaware of the birth, in which case the time limit begins to run on the day he becomes aware of it. The mother may contest the paternity of the presumed father within one year from the birth of the child.