Melnick explains the "third status" of the self by identifying it with intellectual action that does not arise in the progression of attending (and so is not appearance), but accompanies and unifies inner attending. As so accompanying, it progresses with that attending and is therefore temporal--not a thing in itself.
"Melnick's book is rich as an interpretation of Kant, as a study of phenomenology, and as a fairly revisionary picture of metaphysics...Activity-based interpretations of Kant's view on the self have been suggested elsewhere by others, but none has been fleshed out in the way Melnick's is here. As Melnick shows, there are important reasons why such a reading of Kant is appealing, and any commentator wrestling with Kant's views on the self would do well to consider carefully Melnick's contribution to the literature." - Colin Marshall, New York University, USA