Help: H1B renew in process, should I use EAD?

Hi, I have been applying H1B renew from 8 weeks ago through my employer. However, so far I haven't received the receipt yet from USCIS. My old H1B will expire next week. If by that time, I still can not get the recipt, should I use EAD based on my pending 485? If yes, will the H1B approval affect my 485 or my EAD will affect my H1B approval?

Thanks so much!
Any suggestion will be greatly appreciated.