儿子现在是H4， 在加州上大学。明年二月份就21岁了要转F1。记得8老师说只要21岁前寄出申请表就可以了，可一个律师说要在21岁前拿到批准才行。那一个正确呢？
-Doesn't matter as long as his F1 starting date in the I-20 is on/before his 21th birthdate. Your child's H4 status will expire on the date he turns 21. But if he files (USCIS recieve it) the change of status application before he turns 21, he will be lawfully present during the change of status application pending. Then, his status will be F1 on the date indicated in the I-20 when the application is approved.
因为考虑儿子交州内学费的问题，想尽量拖到最后才转F1。如果提前几个月申请，但要求21岁那天（或前2天）再生效可以吗？
-Fine. Indicate it on the I-20. Talk to the school international student office.
