Include Private Notes in Completed Order Email

In our shop which links with an outside distribution network, when orders are completed the customers order details are updated with tracking code and tracking number. I would like this to be added to the completed email that is sent to the customer so they can track delivery. I have searched all through the forums, etc and tried several code snippets to add order notes but none seem to work. My feeling is that in this instance the Distribution company is adding the shipping details as an Order Note but as it has a purple background it must be adding it as a ‘private note’ so solutions I have found so far are unable to grab the information in the private notes.

I would really like either code to add it to the customer_completed_order file in my child theme, or a function to add to my child theme functions file that will generate this private note. I realise it will generate other ‘private notes’ too but that usually reinforces what the client already knows.

The important thing is we don’t want to have to manually send the tracking information, but want it automated.

I appreciate any help you can give with this.

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