I am currently working on H1B visa. I plan to quit my job and get transferred from H1B to H4B. If I submit H4B application in the mid June, and quit the job by the end of June, will I be out of status during the period from the end of June until USCIS approved my H4B case (I heard it normally takes two months for USCIS to process the H4B applications)?

Your status will be fine as long as your H-4 application is filed and accepted before your current employment ends.

Thank you very much for your reply!