Well worth noting the details here in @Hatrack's above post and...

Well worth noting the details here in @Hatrack's above post and why it is the Company has gone down this path with Boeing for eventual FAA approval of CVM. But first it is not about getting a blank approval from Boeing for fitting CVMs either anywhere on the air frame or installation of CVM at air frame build time.- which I must admit I thought this was the case until I re-read Hatrack's post again.
Out of all this Boeing will issue a Service Bulletin which will be eventually approved by the FAA. A Service Bulletin advises the operator on what may be done to service the aircraft and in this case it will be to allow US operators to fit CVM sensors at the APB and thus comply with overall air worthiness directives. Operators in other countries will need approval from their own regulatory bodies but given FAA has made their approval the other regulators basically tick the box. Note that there are more than 700 of these aircraft world wide to potentially fit CVM.
The alternative that SMN could have followed would have been to work with an operator such as Delta and go with them to the FAA for an Alternative Method of Compliance - AMOC. However an AMOC is specific to an operator thus for all other operators SMN would have to apply with them for their own AMOC - time taken to do this apparently longer than the tedious process Boeing currently choosing to follow, - although I have to admit going to the FAA with Delta would have been nice but for that approach you still need time ie we are now into year two with Delta gaining knowledge with the current working CVM. How much 'use' time might the FAA require before it approved an AMOC for Delta? No doubt a lot of time taking interaction between Delta and the FAA before eventual approval.

Rock and hard place comes to mind as to which is the best approach to take.

My presumption - given it is now committee meetings and paperwork back at Boeing to allow them to develop their SB my guess is that SMN will
engage with Airbus sooner than we might have expected.

cheers

redgum