That's all fine and dandy. I just got the impression that you believed all these stories were languishing in a drawer somewhere, and were found, dusted off, and published after the author's death. Such is not the case—not for all
of them anyway.
The collection you mention does
contain two posthumously published works: the first and the last. The last was first published as a fragment in 1968 and then completed by another author (J. Ramsey Campbell) and republished in 1979