This is much needed!
Currently, I have to choose between encrypting notes and being able to add attachments and use full library search.
ADP compatibility would finally solve this issue.
I think some people in another thread ( Will Bear get zero knowledge encryption with iCloud Advanced Data Protection?) already suggested that devs can make ADP opt-in — so that users with older OS versions won’t be affected by the new feature.
Hope we’ll get an update from the devs soon…