I echo support for options 1 & 2.
I think it should be included in the main release notes, since then we don't have to check multiple sources of truth for the current state of affairs, however not clearly marking those items that are API only, is misleading - especially for less experienced or technical customers who may not (yet) have dived into the world of APIs.
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Paul Simpson
Views expressed are my own and do not necessarily reflect those of my employer.
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