Wax Hang Up vs Tunneling
You can expect to find a thin ring of wax around the jar until you get about halfway through the candle. As the candle burns lower, and the heat inside the jar increases, this hang up will slowly be incorporated back into the melt pool.
We use a blend of coconut wax with a touch of paraffin, which you can learn more about here. The same way that honey sticks to the sides of the container, coconut wax has a higher viscosity than many other waxes. Because of this, coconut wax candles have "hang up" around the edges of the candle jar, which is very different than tunneling.
You will never find one of our candles to tunnel, but you probably will find some hang up around the edges.