Auto numbering for both CAD centric and Part centric approach

I'm playing around with auto-numbering in my dev environment.

For most things in production we'll do a File/New in CAD and then auto-associate/create new WTPart on checkin. That works just fine. 

For some cases, we'll create the WTPart first (or have a manufacturing view). 

In auto-numbering with the part-centric approach, if I create a new WTPart and check the "Create CAD" box both end up having the same Number value based on my sequence and naming. So that works fine. 

Keeping the same rules in place, File/New (in NX) creates the correct next in sequence number to replace the file name on save (from Help Center). On upload or check-in though, the auto-associate to create a new WTPart generates the new in sequence value for the Number. The name is fine (same as CAD). 

This appears to be OOTB expected behavior (Help Center )

Is there a way to turn off auto-numbering for WTParts when the CAD is creating it via auto-associate (CAD centric approach) and have it be on when WTPart is created standalone or with associated CAD (Part centric approach)?

Is this a "novel" ask? Seems like you'd want an easy "oh, you're creating a Part first with CAD --> here's a number for both" and "oh, now you're doing CAD first... here's the WTPart that matches the number" option. 

There was this from about a decade ago. If this is still accurate, that means there'd need to be 2 part types each with it's own OIR. One has autonumbering turned on (the soft type) and the other (the root type of WTPart if OOTB auto-associate) has it turned off. 

Does anyone else run auto-numbering in this fashion? Is this the only way to go?