Is it advisable to file an L1 extension if L1-B to H1 COS has already been filed?

I am currently on L1B status with expiry Feb 2022.
I have an approved I-129, and my H1 COS has already been filed in June 2021.
My I94 is valid will Feb 2022, and my employer is the same.

In this case, is it advisable to file an L1 extension? Does the rejection of the L1 extension impact the H1 COS?
Or can H1 COS get rejected even with approved I 129?

Any help with this case is highly appreciated.

Thank you!

The L1 result should not affect H1B application result.