Check temporary permissions separately to the sync task

common/src/main/java/me/lucko/luckperms/core/PermissionHolder.java

@@ -468,12 +468,16 @@ public abstract class PermissionHolder {
 
     /**
      * Removes temporary permissions that have expired
+     * @return true if permissions had expired and were removed
      */
-    public void auditTemporaryPermissions() {
-        this.nodes.keySet().stream()
+    public boolean auditTemporaryPermissions() {
+        List<String> toExpire = this.nodes.keySet().stream()
                 .filter(s -> s.contains("$"))
                 .filter(s -> DateUtil.shouldExpire(Long.parseLong(Patterns.TEMP_DELIMITER.split(s)[1])))
-                .forEach(s -> this.nodes.remove(s));
+                .collect(Collectors.toList());
+
+        toExpire.forEach(s -> this.nodes.remove(s));
+        return !toExpire.isEmpty();
     }
 
     private Map<String, Boolean> convertTemporaryPerms() {

common/src/main/java/me/lucko/luckperms/runnables/ExpireTemporaryTask.java

@@ -0,0 +1,53 @@
+/*
+ * Copyright (c) 2016 Lucko (Luck) <luck@lucko.me>
+ *
+ *  Permission is hereby granted, free of charge, to any person obtaining a copy
+ *  of this software and associated documentation files (the "Software"), to deal
+ *  in the Software without restriction, including without limitation the rights
+ *  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ *  copies of the Software, and to permit persons to whom the Software is
+ *  furnished to do so, subject to the following conditions:
+ *
+ *  The above copyright notice and this permission notice shall be included in all
+ *  copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ *  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ *  SOFTWARE.
+ */
+
+package me.lucko.luckperms.runnables;
+
+import lombok.AllArgsConstructor;
+import me.lucko.luckperms.LuckPermsPlugin;
+import me.lucko.luckperms.core.PermissionHolder;
+import me.lucko.luckperms.groups.Group;
+import me.lucko.luckperms.users.User;
+
+@AllArgsConstructor
+public class ExpireTemporaryTask implements Runnable {
+    private final LuckPermsPlugin plugin;
+
+    @Override
+    public void run() {
+        boolean changes = false;
+        for (Group group : plugin.getGroupManager().getAll().values()) {
+            if (group.auditTemporaryPermissions()) {
+                changes = true;
+            }
+        }
+
+        if (changes) {
+            plugin.runUpdateTask();
+            return;
+        }
+
+        plugin.getUserManager().getAll().values().stream()
+                .filter(PermissionHolder::auditTemporaryPermissions)
+                .forEach(User::refreshPermissions);
+    }
+}