Thank you for your response Mr Woods.
It seems my call to implement an antenna offset specifically for PPK results has been asked before:
https://community.pix4d.com/t/4886-Accounting-for-GPS-antenna-offset#gsc.tab=0
In one post, user Mark, presumably has inside knowledge of the workings of Pix4D and offers that such a tool would be available.
Using the image properties editor is not a solution since there is a fair bit of calculation do be done in order to shift antenna coordinates. Especially when the flight path is considered arbitrary.
Mr Woods, it seems you are not understanding that PPK processed image geolocation coordinates are processed to cm level and are in no way similar to the coarse flight controller derived coordinates. I would agree with your statement about the accuracy of models using flight controller tags only in modelling. How ever, there is much documentation show that PPK processed images are provide acceptable accuracy with out GCP and even better accuracy when combined with GCP.
I hope you will revisit this query with more information and understanding of the problem that your competitors have resolved and applied to their workflow.