derivative applicant family CSPA?

[motopokep]

I am a US citizen, filed I-130 for my adult married son in August of 2010, petition approved in April of 2014, so pending 3.59 years. Visa number in the F3 category will be available in April of this year. My granddaughter will turn 21 years of age in mid-April. The earliest the visa interview can be scheduled is end of April after she will turn 21. Will she age out or not? According to some sources I read, the principal applicant's parent's interview must occur prior to derivative applicant's 21 birthday for derivative not to age out. However, USCIS website has information that CSPA also applies to derivatives and to subtract the number of years the I-130 has been pending from their age at time of interview, so does that mean my granddaughter will not age out as her CSPA age will be 17.5 years at time of interview? Thank you.

[newacct]

What matters is not the time of the interview, but the time a "visa number becomes available", i.e. the first month where the visa bulletin shows a date that is later than their priority date. If they are doing Consular Processing for an immigrant visa, the Final Action Date chart is used. Yes, under CSPA, the length of time the I-130 was pending is subtracted from her age at the time a visa number becomes available.

[motopokep]

What matters is not the time of the interview, but the time a "visa number becomes available", i.e. the first month where the visa bulletin shows a date that is later than their priority date. If they are doing Consular Processing for an immigrant visa, the Final Action Date chart is used. Yes, under CSPA, the length of time the I-130 was pending is subtracted from her age at the time a visa number becomes available.

thank you. Trying to understand this better, since I-130 was pending or 3.5 years, the child would still not age out if the visa number became available let's say 3 years from now, as the child would have been 20.5 at time of visa availability?

[newacct]

thank you. Trying to understand this better, since I-130 was pending or 3.5 years, the child would still not age out if the visa number became available let's say 3 years from now, as the child would have been 20.5 at time of visa availability?

correct