diff --git a/Make.config b/Make.config
index ebd73bb8ba..2d7a3ec0ec 100644
--- a/Make.config
+++ b/Make.config
@@ -29,7 +29,7 @@ PACKAGE_HEAD_REV=$(shell git rev-parse HEAD)
 # on wrench, because wrench technically builds hashes, not branches)
 #
 # 
-PACKAGE_HEAD_BRANCH=xcode8
+PACKAGE_HEAD_BRANCH=xcode8.1
 ifeq ($(BUILD_REVISION),)
 CURRENT_BRANCH:=$(shell git rev-parse --abbrev-ref HEAD)
 else
@@ -67,9 +67,9 @@ MIN_OSX_BUILD_VERSION=10.11
 MIN_OSX_VERSION_FOR_IOS=10.10
 MIN_OSX_VERSION_FOR_MAC=10.10
 
-IOS_SDK_VERSION=10.0
+IOS_SDK_VERSION=10.1
 OSX_SDK_VERSION=10.12
-WATCH_SDK_VERSION=3.0
+WATCH_SDK_VERSION=3.1
 TVOS_SDK_VERSION=10.0
 
 MIN_IOS_SDK_VERSION=6.0
diff --git a/tests/xharness/AppRunner.cs b/tests/xharness/AppRunner.cs
index 118b87b5c9..1f138fa959 100644
--- a/tests/xharness/AppRunner.cs
+++ b/tests/xharness/AppRunner.cs
@@ -71,28 +71,28 @@ namespace xharness
 			if (simulators != null)
 				return;
 			
-			string simulator_devicetype;
+			string [] simulator_devicetypes;
 			string simulator_runtime;
 
 			switch (Target) {
 			case "ios-simulator-32":
-				simulator_devicetype = "com.apple.CoreSimulator.SimDeviceType.iPhone-5";
+				simulator_devicetypes = new string [] { "com.apple.CoreSimulator.SimDeviceType.iPhone-5" };
 				simulator_runtime = "com.apple.CoreSimulator.SimRuntime.iOS-" + Xamarin.SdkVersions.iOS.Replace ('.', '-');
 				break;
 			case "ios-simulator-64":
-				simulator_devicetype = "com.apple.CoreSimulator.SimDeviceType.iPhone-5s";
+				simulator_devicetypes = new string [] { "com.apple.CoreSimulator.SimDeviceType.iPhone-5s" };
 				simulator_runtime = "com.apple.CoreSimulator.SimRuntime.iOS-" + Xamarin.SdkVersions.iOS.Replace ('.', '-');
 				break;
 			case "ios-simulator":
-				simulator_devicetype = "com.apple.CoreSimulator.SimDeviceType.iPhone-5";
+				simulator_devicetypes = new string [] { "com.apple.CoreSimulator.SimDeviceType.iPhone-5" };
 				simulator_runtime = "com.apple.CoreSimulator.SimRuntime.iOS-" + Xamarin.SdkVersions.iOS.Replace ('.', '-');
 				break;
 			case "tvos-simulator":
-				simulator_devicetype = "com.apple.CoreSimulator.SimDeviceType.Apple-TV-1080p";
+				simulator_devicetypes = new string [] { "com.apple.CoreSimulator.SimDeviceType.Apple-TV-1080p" };
 				simulator_runtime = "com.apple.CoreSimulator.SimRuntime.tvOS-" + Xamarin.SdkVersions.TVOS.Replace ('.', '-');
 				break;
 			case "watchos-simulator":
-				simulator_devicetype = "com.apple.CoreSimulator.SimDeviceType.Apple-Watch-38mm";
+				simulator_devicetypes = new string [] { "com.apple.CoreSimulator.SimDeviceType.Apple-Watch-38mm", "com.apple.CoreSimulator.SimDeviceType.Apple-Watch-Series-2-38mm" };
 				simulator_runtime = "com.apple.CoreSimulator.SimRuntime.watchOS-" + Xamarin.SdkVersions.WatchOS.Replace ('.', '-');
 				break;
 			default:
@@ -107,7 +107,7 @@ namespace xharness
 				await sims.LoadAsync (Logs.CreateStream (LogDirectory, "simulator-list.log", "Simulator list"));
 			}).Wait ();
 
-			var devices = sims.AvailableDevices.Where ((SimDevice v) => v.SimRuntime == simulator_runtime && v.SimDeviceType == simulator_devicetype);
+			var devices = sims.AvailableDevices.Where ((SimDevice v) => v.SimRuntime == simulator_runtime && simulator_devicetypes.Contains (v.SimDeviceType));
 			SimDevice candidate = null;
 			simulators = null;
 			foreach (var device in devices) {
@@ -134,7 +134,7 @@ namespace xharness
 			}
 			if (simulators == null) {
 				if (candidate == null)
-					throw new Exception ($"Could not find simulator for runtime={simulator_runtime} and device type={simulator_devicetype}.");
+					throw new Exception ($"Could not find simulator for runtime={simulator_runtime} and device type={string.Join (";", simulator_devicetypes)}.");
 				simulators = new SimDevice [] { candidate };
 			}
 
diff --git a/tests/xharness/Jenkins.cs b/tests/xharness/Jenkins.cs
index f29fbce223..9b871ea9a6 100644
--- a/tests/xharness/Jenkins.cs
+++ b/tests/xharness/Jenkins.cs
@@ -78,15 +78,19 @@ namespace xharness
 							  Where ((SimRuntime v) => v.Identifier.StartsWith ("com.apple.CoreSimulator.SimRuntime.watchOS-", StringComparison.Ordinal)).
 							  OrderBy ((SimRuntime v) => v.Version).
 							  Last ();
-				var watchOSDeviceType =
+				var watchOSDeviceTypes =
 					Simulators.SupportedDeviceTypes.
-							  Where ((SimDeviceType v) => v.ProductFamilyId == "Watch").
-							  First ();
+							  Where ((SimDeviceType v) => v.ProductFamilyId == "Watch");
 				var devices = 
 					Simulators.AvailableDevices.
-					          Where ((SimDevice d) => d.SimRuntime == latestwatchOSRuntime.Identifier && d.SimDeviceType == watchOSDeviceType.Identifier);
+					          Where ((SimDevice d) => d.SimRuntime == latestwatchOSRuntime.Identifier && watchOSDeviceTypes.Any ((v) => d.SimDeviceType == v.Identifier));
 				var pair = Simulators.AvailableDevicePairs.
 				              FirstOrDefault ((SimDevicePair v) => devices.Any ((SimDevice d) => d.UDID == v.Gizmo));
+				if (pair == null) {
+					var msg = string.Format ("Could not find a device pair for any of these devices: {0}", string.Join (", ", devices.Select ((v) => v.Name).ToArray ()));
+					SimulatorLoadLog.WriteLine (msg);
+					throw new Exception (msg);
+				}
 				var device =
 					Simulators.AvailableDevices.
 							  FirstOrDefault ((SimDevice v) => pair.Gizmo == v.UDID); // select the device in the device pair.