H1b extension along with I 140

Hi. My H1 is due for extension in October. My perm is filed in Feb and expecting an approval around August- September. Do u think it makes sense to wait for perm and then file extension and i140 together or can I just go with extension now ? My max out is Aug 2023, so if I do apply my extension without getting perm then I would only get approval till Aug 2023 and will have to re do again after i140 is approved.
And if I do them together in premium , should I pay premium fee separately for each one or does it go together ?
Please help clarify .Thank you.