It looks like the Shelly device initiates contact with home assistant you may be able to just tell it to talk to the same api endpoint (following is for 2nd gen devices):

In this case, navigate to the local IP address of your Shelly device, Settings >> Connectivity >> Outbound WebSocket and check the box Enable Outbound WebSocket, under server enter the following address:

ws:// + Home_Assistant_local_ip_address:Port + /api/shelly/ws (for example: ws://192.168.1.100:8123/api/shelly/ws), click Apply to save the settings. In case your installation is set up to use SSL encryption (HTTPS with certificate), an additional s needs to be added to the WebSocket protocol, too, so that it reads wss:// (for example: wss://192.168.1.100:8123/api/shelly/ws).

Assuming you are buying a new unit I’d try following that guide after backing up and seeing if it updates normally. The first gen devices used a different protocol, full instructions for both can be found here.