AFAIK, even the C09 category gets automatic extension of 180 days. My EAD/AP is pending since Nov '19. And, our current ones expire next month. Our lawyer told us there's an automatic 180 days extension for our EADs.
Fragoman is right. Filing Supplement J is not mandatory to when you change job on AOS. You have to be ready to file it when they send you an RFE or NOID. But, some law firms ask you to file it proactively to avoid any last minute surprises when you get an RFE (Just to be on the safer side).