Qui parle ? Des « livres futurs » de Proust et de Butor

At the end of Le Temps retrouvé, the Proustian hero-narrator, after defining his aesthetic principles, announces his decision to devote himself to writing novels. In the same way, having resolved to modify the modification he had implemented over the course of his life, Leon Delmont claims to want to resume his story in a “future book.” In both cases, does this end constitute a coup d’écriture, referring the reader to the beginning of the work he has just completed?