Well! My Galaxy S5 got a big OTA update,

Round Custom Faces
1

Well! My Galaxy S5 got a big OTA update, and ever since that my K8 Mini has stayed connected. Liking this watch better and better.

2

Are you talking about BT tethering?

3

Watch Helper has not been able to stay connected since I got the watch. With this update, it stayed connected for several days, and re-starting the phone got the connection back again.