Native MQTT / 3.12.0-rc.1 timestamp

Hi, I modded rabbitmq-message-timestamp to be usable with 3.12.0-rc.1 and MQTT Native qos0.

In my actual 3.11 use case i collect iot information with MQTT plugin and process them with amqp connections.

I use publish time of received MQTT messages as timestamp with plugins message_timestamp_in_ms.

My problem is the following: 

– in mqtt there is no timestamp in messages.

– plugin message time stamp is base on channel interceptor  and it seeems MQTT native plugin does not declare channels.

How could my rabbitmq server add server referenced timestamp to messages collected in mqtt with 3.12 ? 

Is it possible with 3.11 and i wish 3.12 to get timestamp of messages in MQTT without modifying payload ?

Regards,