Random "HTTP 503 Unavailable"

No, it’s not solved in a matter of hours because the bridge can handle only one connection at a time and if you don’t serialize at your end the API will always throw 503 errors (or timeouts if we restrict the HTTP server to just one HTTP connection). This is something that’s not going to go away, ever. If you can not properly serialize you’re better off using the Nuki Web API, where we do the serialization at our end.