Good question that I would like an answer to as well!
While I have the FAQ and the framework documentation, I can find nothing suggesting where/how one gets permission.
I am not a public health agency. I am not even (at this time) wanting to write an app for a public health agency. What I am trying to accomplish is writing enabling code - extension/adaptation layer for a cross-OS e.g. iOS/Android development platform (think like PhoneGap/Cordova/Xamarin/React Native, though none of the above but same idea...) that will enable PHAs (and those they might hire/contract with) to write apps using that platform without having to each reinvent the wheel by writing native code to connect to the Exposure Notification framework.
I've not found anything from search, so it begs the question as to how even public health agencies will get the permission? Is Apple proactively reaching out? If so, how will they even know who to reach out to? Are they calling agencies and asking "I want to talk to whoever is in charge of writing mobile apps"? (Which in most cases will be.... wait for it... nobody!) Are the PHAs trying to reach out to Apple? If so, they must be having the same difficulty I am!
Any help with contact information, and something more than press releases, FAQs and Framework Documentation would be appreciated!
I presume there is some test system to connect to for development?
FWIW, I have a sponsor for the work I intend to do, and I will have the cooperation of the cross-platform tool vendor. And it will be open-sourced and placed under MIT license. But it's in an odd niche, because it is not an app, it is just a layer enabling others to write an app.
Any idea who I approach at Apple?