Can I transfer from f4 to f3 when I immigrate to America?

Types of visa applications for overseas families of American citizens

F3: Immigration visa for married children of American citizens.

F4: American citizen's brother and sister immigrant visa

If F4 in the United States is scheduled to apply for replacing F3, according to the immigration law of the United States, it cannot be directly transferred, because the types of immigrants are different and the sponsors are different, so it cannot be directly transferred. If you really need to transfer, cancel the F4 application, then reapply for the F3 immigration category and queue up again. The previous queue time is invalid.