Docker setup with Shelly and CoIoT

Update: I found out that HA actually IS listening on that port, but on UDP:

/config # netstat -an | grep 5683
udp        0      0 0.0.0.0:5683            0.0.0.0:*

so I updated my docker-compose.yml accordingly:

    ports:
      - "5683:5683/udp"

and made sure the configuration worked:

$ docker-compose ps
             Name                Command   State           Ports
-------------------------------------------------------------------------
home-assistant_homeassistant_1   /init     Up      0.0.0.0:5683->5683/udp

However, the issue STILL persists, it takes forever until HA picks up the state change of any of the switches. Is there a way I can debug what HA is receiving there so I can find out if the Shelly is actually broadcasting stuff there?