New 'Managed' option under Store Availability does not give a Business release channel

The new 'Store Availability' allows us to enable the 'Managed' option for our app.
We enabled this in order to be able to do app distribution on Meta for Work & Meta for Education.

Enabling this did not give us a 'Business' release channel. This is required in order for us to be able to add the Meta for Work organisation. Such a channel does appear for newly created 'private' apps.

Does anyone know a way to add a Business release channel to an existing app? -,This new 'Store Availability' option would suggest there should be a way. 🤔