First of all: plugins

Even though the whole functionality is implemented inside the component you need a way to forward messages with AMP payload to that component. This is what the amp plugin does. The amp plugin intercepts all <message/> packets even without AMP payload, redirecting some of the to the AMP component and others processing in a standard way. Therefore you no longer need message plugin or msgoffline plugin. Those are all functions are offered by the amp plugin now. Hence you have to switch message and msgoffline plugins off (the amp plugin is loaded by default):

'sess-man' {
    amp () {}
    message (active: false) {}
    msgoffline (active: false) {}
}

The amp plugin needs to know where to forward all the AMP packets. By default plugin uses hostname of the given machine as this is true to the most installations. However, this is configured by the last line of the example configuration, which forwards all packets to the address amp@your-domain.tld:

'sess-man' {
    amp () {
        'amp-jid' = 'amp@your-domain.tld'
    }
}