Copy comment from Private Note to Note to Customer

Currently my shipping service provider will auto update the order status from ‘processing’ to ‘completed’, and then add a private note with tracking info “eg: Courier: 1233459112843”. So this will trigger the order completed email customized by Yaymail Pro.

How do I:

1. Copy the comment from ‘private note’ to ‘note to customer’? So that the customer will receive an email containing the tracking code. OR
2. Add a delay to send out order completed email, then check the private note if it contain the courier name, if yes, add this comment into the order completed email.

Thank you so much for the help.