The post is actually created first and then the fields are updated after the post creation is complete.
The storing of the field value correctly seems to be the problem. Swapping to YYYYMMDD works but for some reason I still need to open the post and re-save for it to the start returning it as DD/MM/YYYY. It is like ACF if doing something else once it laods and resaves the value from YYYYMMDD.
Is there a way of saving it YYYMMDD but without having to then go into the post and resaving for it to return it in the other value?
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