3.1.5 Message Processing Events and Sequencing Rules

If the client receives a RopNotify ROP response ([MS-OXCROPS] section 2.2.14.2) for the event subscription specified in section 3.1.3, it SHOULD obtain a new copy of the mail add-in manifest using the GetAppManifests operation specified in [MS-OXWSCEXT] section 3.1.4.2.