Be careful travel without AP!

Although you can use H4 to return to USA, and not
using AP. However, your I-485 is pending, once you
go outside of USA, your I-485 will be invalid if
you do not have an AP!
So be careful, if you decide to travel outside of
USA, you have to apply for an AP. You can choose not
to use it, but you have to hold it before you leave
USA. Otherwise, your I-485 will not be valid if you
go abroad.