We've had alot of users leverage our Limited Modular Approval (LMA) described here: Broadcom CYW2073XS SiP Module Regulatory Approvals via a Letter of Authorization (LOA), but none have requested the firmware rev, because as you stated, the core firmware and stack is loaded in ROM and RF parameters related to regulatory cannot be changed by the user.
A0 Firmware = BCM20732S
A1 Firmware = BCM20736S, BCM20737S
Let me know if this addresses your question.
Yes, It does. Many thanks for Your help!