After you submit I-485, can you forget about H1B?

I -485 is one of the process when you apply green card. It means that you have intention of immigration. After that, a lot of people also apply EAD (work permit) without renew your H1-B( if your H1b is going to expire). You should still keep your H1B and renew it because you do not know the final result of your green card application. If you fail( hope not), you still have H1B visa status and try to apply your green card again (or ask your spouse to try if you have one). Otherwise, you do not have any back up plan.