How did my Samsung non LTE watch receive real time texts and let me reply when my phone was 5 miles away? I received two texts on my watch ,which was on my wrist, from an associate who was at my work location. My phone was also at the same work location 5 miles away. There is no wifi at the work location.
So that must be using "Remote connection". It connects via our Samsung account. In your case the phone would be using mobile network and the watch using WiFi. "Remote connection" is switch on/off in the wearable app.