I can reproduce this, and my fix is: open Simulator, look at the top menu and go to: Hardware -> Device -> Manage Devices. There you can see a list of available simulator “instance”, just delete them all except for the one that you are targeting for test
@tbao, yes i know a couple work arounds, could even use udid but that is not my expectation and are not stable solutions. Appium should handle this and come up with new capabilities or some for the watch sims. thanks for confirming the bug.