JUCE will only take care of building, the signing step is completely separate.
You have to get in touch with PACE. They will provide you with their bespoke signing tool (wraptool), and it will use your certificate to sign (either the Apple Dev cert or any certificate, that is accepted by their/ProTools CA.
For development, AVID provides a debug build, that allows to run unsigned plugins, if you are in the development programme.
I am just telling the common knowledge, the details might be covered under NDA, so sorry for not answering in more detail.