H4 EAD application is Pending with USCIS

H4 EAD applied on July-20 request pending with USCIS.
H4 Visa Valid until Mar-21

October I am planning to submit H1 & H4 Extension, shall I apply H4 EAD again so I can get the EAD with few more years, or do I have to wait for my previous EAD application status to apply for a new one?