Apple have added a new entitlement com.apple.developer.contacts.notes which allows apps to access the notes field of the contact db. The new entitlement is on a per app basis with developers required to put their case to Apple to gain it.
Titanium requests CNContactNoteKey as part of the Ti.Contacts.getAllPeople method. This triggers a CNErrorDomain error 102.
Any app compiled for iOS 13 without this entitlement will not be able to use the Ti.Contacts module for anything; regardless of needing the notes field.
To test create an empty project with the following in tiapp.xml
Add the following to alloy.js
var people = Ti.Contacts.getAllPeople();
error in console