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UPGRADE.md

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+Upgrading instructions for Yii2-user
+====================================
+
+The following upgrading instructions are cumulative. That is, if you want to upgrade from version A to version C and
+there is version B between A and C, you need to following the instructions for both A and B.
+
+Upgrade from Yii2-user 0.8.0
+----------------------------
+
+- `webUserClass` module option has been dropped. If you are using custom user component you should set in `user`
+application component configuration:
+
+```php
+'components' => [
+    'user' => [
+        'class' => 'your\web\User',
+    ],
+],
+```
+
+- ModelManager component has been dropped. If you are using custom models you should set them via `modelMap` module's
+property:
+
+```php
+'modules' => [
+    'user' => [
+        'class' => 'dektrium\user\Module',
+        'modelMap' => [
+            'User' => 'your\model\User',
+            'Profile' => 'your\model\Profile',
+            ...
+        ],
+    ],
+],
+```