diff -u b/core/modules/update/src/ProjectSecurityData.php b/core/modules/update/src/ProjectSecurityData.php
--- b/core/modules/update/src/ProjectSecurityData.php
+++ b/core/modules/update/src/ProjectSecurityData.php
@@ -176,7 +176,7 @@
    * - The latest available official release of that project.
    * - The target minor release where security coverage for the current release
    *   should expire. This target release is determined by
-   *   static::getSecurityCoverageUntilVersion().
+   *   getSecurityCoverageUntilVersion().
    *
    * The Drupal Security Team policy is currently to provide security coverage
    * for 2 minor release cycles. Some examples of how this function behaves:
@@ -202,7 +202,7 @@
    *   The number of additional minor releases that receive security coverage,
    *   or NULL if this cannot be determined.
    *
-   * @see static::getSecurityCoverageUntilVersion()
+   * @see \Drupal\update\ProjectSecurityData\getSecurityCoverageUntilVersion()
    */
   private function getAdditionalSecurityCoveredMinors($security_covered_version) {
     $security_covered_version_major = ModuleVersion::createFromVersionString($security_covered_version)->getMajorVersion();
@@ -211,7 +211,7 @@
       $release_version = ModuleVersion::createFromVersionString($release['version']);
       if ($release_version->getMajorVersion() === $security_covered_version_major && $release['status'] === 'published' && !$release_version->getVersionExtra()) {
         // The releases are ordered with the most recent releases first.
-        // Therefore, if we have found a published official release with the
+        // Therefore, if we have found a published, official release with the
         // same major version as $security_covered_version, then this release
         // can be used to determine the latest minor.
         $latest_minor = $this->getSemanticMinorVersion($release['version']);
@@ -220,7 +220,7 @@
     }
     // If $latest_minor is set, we know that $security_covered_version_minor and
     // $latest_minor have the same major version. Therefore, we can subtract to
-    // determine the number of additional minor security covered releases.
+    // determine the number of additional minor releases with security coverage.
     return isset($latest_minor) ? $security_covered_version_minor - $latest_minor : NULL;
   }