How can we protect our son from aging out?

Make sure you pay the NVC fee invoice immediately after receiving it. The NVC may give you trouble with issuing the invoice to the child because of potential age-out, but an experienced immigration attorney should be able to help you work with the NVC to get that sent.

Generally, under CSPA, you will be able to subtract the time I-526 has been pending, including RFE adjudication, from your child's age as you had filed before the child turned 21. However, given the current immigrant visa backlog for mainland Chinese nationals, it is possible your child may age out. You may prolong responding to the RFE and file a response close to the deadline to drag on some time, but ensure it is timely received by USCIS to avoid denial of the I-526. If USCIS opens Chart B, there may be opportunity if the I-526 is approved post-RFE response. You should discuss with your immigration attorney. You generally have one year to pay the immigrant visa fee and file the DS-260 for the child or file for adjustment of status if in the United States for the child to be considered to have sought to acquire permanent residence.

According to the Child Status Protection Act, your son's age for the purposes of determining whether he still is a dependent (and therefore included in your case) will be determined by taking his age on the date an immigrant visa number becomes available (i.e., the date your priority date becomes current) and subtracting the amount of time your I-526 was pending (filing date/priority date until approval date). Therefore, it might be a good strategy to wait to file your RFE response until the last day or two before it is due. This may buy you a little more time. Also, it is very important that you "seek to acquire" an immigrant status within one year of the priority date becoming current. You can do this by paying the immigrant visa fee bills and submitting Forms DS-260 as soon as you are instructed to do so by the National Visa Center (after I-526 approval).

Retrogression is a serious issue, particularly for petitioners from the People's Republic of China. You may only include your unmarried son under the age of 21. Since you filed your petition on July 22, 2014, when your son was still three days from being 21, having been born on July 25, 1993, under the Child Status Protection Act, as long as you filed while your son was under 21, he is protected as long as the petition is pending and is not yet adjudicated. Thus, in your case, you would want to delay any response to your RFE as long as legally possible and hope that USCIS takes as much time as possible to decide your case. However, given the fact that your petition could be approved anytime in the next 12 months, and it is likely that the backlog and visa numbers for Chinese nationals could be several more years; it is possible that your son will age out and lose his eligibility to immigrate as your EB-5 dependent. There is nothing you can do at this time regarding your current petition other than again, hoping for a very lengthy delay on the part of USCIS in adjudicating and making a final decision on your EB-5 petition. You could, of course, file a separate I-526 EB-5 petition in the name of your son, but that would require an additional investment.

The CSPA provides relief for children who would have maintained eligibility but for the time United States Citizenship and Immigration Services (USCIS) took to adjudicate the immigrant visa petition. This relief takes the form of subtracting the time the petition was pending from the child's age; this is the child's "CSPA age." Provided that the child's CSPA age is under 21 at the time the immigrant visa is issued to the principal, the child will not be ineligible to receive a visa based on age, even if the child's real age has reached 21. In terms of retrogression, absent a huge backlog, if the child's CSPA age is under 21 at the time the priority date becomes current, and the child takes a step toward pursuing that immigrant visa within one year of becoming current, such as filing an I-485, then the child's age is "locked-in," and he or she will be protected from aging-out. Those most vulnerable are those who are near the age of 21 at the time of the I-526 filing and whose CSPA age may reach 21 before the priority date is current. Contact a qualified immigration lawyer to discuss.

If his filing date is current, you can file for his adjustment of status.

If you are subject to the Chinese quota and filed three days before your son's birthday, there is very little chance of avoiding an age-out. The RFE is a good thing, as you get to deduct all the time the petition is pending. Reply on the last day. However, you need to have the petition pending longer than the waiting line, which is currently 28 months, but is practically frozen now. So presently you are a few months short, but the waiting line is also getting longer, so it's very hard to beat it. You can only hope they do not adjudicate the RFE for a few months or you have no chance. Maybe if they open Chart B adjustment filings in October there is a chance, but it is best to ask USCIS to delay adjudication so you can have the case pending longer than the waiting line. You have 12 months to seek to acquire status and the State Department now requires payment of the fee bill and filing DS-260 when the visa is avoidable to freeze the child's age.