Once the principal applicant files their I-526 petition, the age of all their dependents is frozen. At the time of their I-526 of approval, we check whether their country of birth is subject to visa retrogression. There is no age-out issue to worry about if it is not subject to visa retrogression, and the applicant can file for the conditional green card within one year. On the other hand, if it is subject to visa retrogression, the applicant cannot apply for the conditional green card until his priority date becomes current. In this case, the age of their dependents is unfrozen. Depending on the time they need to wait, their dependents could age out. For example, assume that the dependent was 20 years old at the I-526 filing, and after I-526 approval, it takes more than one year for the priority date of the principal applicant to become current. Then the dependent will surely, age-out. The applicant can proceed with the conditional green card application as soon as their priority date becomes current. If their dependent was 20 years old at the I-526 filing, and after I-526 approval, it takes less than one year for the priority date to become current, then the dependent will not age out.