Thank you so much for your response,if USCIS do not agree my Calculation and deny my son's application,
why it will effect my son's future F1 status extension (e.g. transfer school, go to graduate school, OPT application, etc.).
-because the immigration intent will affect his F1 extension if he files I-485.
Will it effect my I-485 application?
-No. Irrelevant.
However, you can use some of the CSPA benefits to retain your priority date for your future sponsoring your son green card application using F2B category (family based) after you get your GC and your son is in H1 status.
See this link for "Retention of Priority Date" part:
