How to get the contact creation date?

Question

Using the new Contact Structure in iOS 9, how can I get the date the contacts were created?

In previous versions, using the address book structure, I could do this:

ABRecordRef person = ...
NSDate *creationDate = (__bridge_transfer NSDate *)ABRecordCopyValue(person, kABPersonCreationDateProperty);

but I could not find the right way to do this using the new structure, CNContactthere is no obvious property and no relevant key.

Disclaimer: This question was originally sent to SO.es , but since I received no answer, I decided to post it here.