If you cannot provide access

This will affect timescales as it limits the dev teams ability to share assets and unable to submit the app on their own.

The client will  be required to

Send: Distribution certificate (.p12)

Created Bundle ID: com.abc.client (have them ensure this was made "push enabled")

Send: Provisioning Profile (have them ensure this was created only after the bundle ID was confirmed to have been configured for push messaging)

Create using attached CSR and send: Production Push Certificate