A valid SEVIS I-20 certificate of eligibility and maintenance of a full-time course load are required for one’s legal status. An F-1 student must make normal progress towards completing the course of study, by completing studies before the expiration of the program completion date on Form I-20. In the event that this is not possible, one should contact the Designated School Official (DSO). There are some limited exceptions to the full-time requirement and the advisor can authorize a lighter course load in appropriate situations, such as in the case of an illness. It is necessary to obtain such authorization in order to maintain status. Additionally, one should ensure that the passport is valid for at least six months into the future, that s/he does not work off-campus without proper authorization, and that s/he applies for an extension of stay if it is found that s/he cannot graduate in the time indicated on the I-20 certificate of eligibility. An international student is required to notify the DSO of a change of address within ten days, and should also notify the DSO if s/he intends to withdraw from school or transfer to a different school.