diff --git a/core/ArchiveProcessor.php b/core/ArchiveProcessor.php
index 493aee771353eda1d99bb8a10f1084e53a25f18c..2be7f239fa841bbe865fe0d633eb30110dd0faa3 100644
--- a/core/ArchiveProcessor.php
+++ b/core/ArchiveProcessor.php
@@ -310,7 +310,7 @@ abstract class ArchiveProcessor
     /**
      * Returns the minimum archive processed datetime to look at
      *
-     * @return string Datetime string, or false if must look at any archive available
+     * @return int|bool  Datetime timestamp, or false if must look at any archive available
      *
      * @public for tests
      */