diff --git a/src/applications/auth/editor/PhabricatorAuthSSHKeyEditor.php b/src/applications/auth/editor/PhabricatorAuthSSHKeyEditor.php
--- a/src/applications/auth/editor/PhabricatorAuthSSHKeyEditor.php
+++ b/src/applications/auth/editor/PhabricatorAuthSSHKeyEditor.php
@@ -197,9 +197,7 @@
 
     // After making any change to an SSH key, drop the authfile cache so it
     // is regenerated the next time anyone authenticates.
-    $cache = PhabricatorCaches::getMutableCache();
-    $authfile_key = PhabricatorAuthSSHKeyQuery::AUTHFILE_CACHEKEY;
-    $cache->deleteKey($authfile_key);
+    PhabricatorAuthSSHKeyQuery::deleteSSHKeyCache();
 
     return $xactions;
   }
diff --git a/src/applications/auth/query/PhabricatorAuthSSHKeyQuery.php b/src/applications/auth/query/PhabricatorAuthSSHKeyQuery.php
--- a/src/applications/auth/query/PhabricatorAuthSSHKeyQuery.php
+++ b/src/applications/auth/query/PhabricatorAuthSSHKeyQuery.php
@@ -11,6 +11,12 @@
   private $keys;
   private $isActive;
 
+  public static function deleteSSHKeyCache() {
+    $cache = PhabricatorCaches::getMutableCache();
+    $authfile_key = self::AUTHFILE_CACHEKEY;
+    $cache->deleteKey($authfile_key);
+  }
+
   public function withIDs(array $ids) {
     $this->ids = $ids;
     return $this;
diff --git a/src/applications/people/editor/PhabricatorUserEditor.php b/src/applications/people/editor/PhabricatorUserEditor.php
--- a/src/applications/people/editor/PhabricatorUserEditor.php
+++ b/src/applications/people/editor/PhabricatorUserEditor.php
@@ -195,6 +195,10 @@
 
     $user->saveTransaction();
 
+    // The SSH key cache currently includes usernames, so dirty it. See T12554
+    // for discussion.
+    PhabricatorAuthSSHKeyQuery::deleteSSHKeyCache();
+
     $user->sendUsernameChangeEmail($actor, $old_username);
   }