You can enter US by a valid H visa or advanced Parole. You have to apply AP when you physically in the States.

Hey, thanks!! I am ready to file 485 now (I can send out all the documents tomorrow!) but my husband, who is going to file with me, is currently outside USA on a business trip. I wonder if I have to wait until he comes back... It's kinda urgent as I want to get a EAD card asap:)

You can file your two case separately. File your application first for your EAD purpose. File for your husband when he come back. That will be safe. What kind of visa your husband is going to use for entering States?

Hey, thanks!! I am ready to file 485 now (I can send out all the documents tomorrow!) but my husband, who is going to file with me, is currently outside USA on a business trip. I wonder if I have to wait until he comes back... It's kinda urgent as I want to get a EAD card asap:)