diff --git a/e2e/test/iothub/service/RegistryManagerE2ETests.cs b/e2e/test/iothub/service/RegistryManagerE2ETests.cs
index e9533c2526..e67c6ca723 100644
--- a/e2e/test/iothub/service/RegistryManagerE2ETests.cs
+++ b/e2e/test/iothub/service/RegistryManagerE2ETests.cs
@@ -392,50 +392,32 @@ public async Task RegistryManager_ConfigurationOperations_Work()
         public async Task RegistryManager_Query_Works()
         {
             // arrange
-            using var registryManager = RegistryManager.CreateFromConnectionString(TestConfiguration.IoTHub.ConnectionString);
-            string deviceId = $"{_idPrefix}{Guid.NewGuid()}";
-
-            try
-            {
-                Device device = await registryManager
-                    .AddDeviceAsync(new Device(deviceId))
-                    .ConfigureAwait(false);
 
-                // act
+            using var registryManager = RegistryManager.CreateFromConnectionString(TestConfiguration.IoTHub.ConnectionString);
+            string deviceId = TestConfiguration.IoTHub.X509ChainDeviceName;
 
-                IQuery query = null;
-                IEnumerable<Twin> twins = null;
-                for (int i = 0; i < 30; ++i)
-                {
-                    string queryText = $"select * from devices where deviceId = '{deviceId}'";
-                    query = registryManager.CreateQuery(queryText);
+            Device device = await registryManager
+                .GetDeviceAsync(deviceId)
+                .ConfigureAwait(false);
+            device.Should().NotBeNull($"Device {deviceId} should already exist in hub setup for E2E tests");
 
-                    twins = await query.GetNextAsTwinAsync().ConfigureAwait(false);
+            // act
 
-                    if (twins.Any())
-                    {
-                        break;
-                    }
+            string queryText = $"select * from devices where deviceId = '{deviceId}'";
+            IQuery query = registryManager.CreateQuery(queryText);
+            IEnumerable<Twin> twins = await query.GetNextAsTwinAsync().ConfigureAwait(false);
 
-                    // A new device may not return immediately from a query, so give it some time and some retries to appear
-                    await Task.Delay(250).ConfigureAwait(false);
-                }
+            // assert
 
-                // assert
-                twins.Count().Should().Be(1, "only asked for 1 device by its Id");
-                twins.First().DeviceId.Should().Be(deviceId, "The Id of the device returned should match");
-                query.HasMoreResults.Should().BeFalse("We've processed the single, expected result");
-            }
-            finally
-            {
-                await registryManager.RemoveDeviceAsync(deviceId).ConfigureAwait(false);
-            }
+            twins.Count().Should().Be(1, "only asked for 1 device by its Id");
+            twins.First().DeviceId.Should().Be(deviceId, "The Id of the device returned should match");
+            query.HasMoreResults.Should().BeFalse("We've processed the single, expected result");
         }
 
         [LoggedTestMethod]
         public async Task ModulesClient_GetModulesOnDevice()
         {
-            int moduleCount = 5;
+            const int moduleCount = 2;
             string testDeviceId = $"IdentityLifecycleDevice{Guid.NewGuid()}";
             string[] testModuleIds = new string[moduleCount];
             for (int i = 0; i < moduleCount; i++)
@@ -458,6 +440,9 @@ public async Task ModulesClient_GetModulesOnDevice()
                         new Module(testDeviceId, testModuleIds[i])).ConfigureAwait(false);
                 }
 
+                // Give the hub a moment
+                await Task.Delay(250).ConfigureAwait(false);
+
                 // List the modules on the test device
                 IEnumerable<Module> modulesOnDevice = await client.GetModulesOnDeviceAsync(testDeviceId).ConfigureAwait(false);
 
@@ -468,7 +453,7 @@ public async Task ModulesClient_GetModulesOnDevice()
                 Assert.AreEqual(moduleCount, moduleIdsOnDevice.Count);
                 for (int i = 0; i < moduleCount; i++)
                 {
-                    Assert.IsTrue(moduleIdsOnDevice.Contains(testModuleIds[i]));
+                    moduleIdsOnDevice.Should().Contain(testModuleIds[i]);
                 }
             }
             finally
diff --git a/e2e/test/iothub/service/RegistryManagerImportDevicesTests.cs b/e2e/test/iothub/service/RegistryManagerImportDevicesTests.cs
index 2ccc77d349..4a7f0ba1e6 100644
--- a/e2e/test/iothub/service/RegistryManagerImportDevicesTests.cs
+++ b/e2e/test/iothub/service/RegistryManagerImportDevicesTests.cs
@@ -43,6 +43,7 @@ public class RegistryManagerImportDevicesTests : E2EMsTestBase
         [DataRow(StorageAuthenticationType.KeyBased, false)]
         [DataRow(StorageAuthenticationType.IdentityBased, false)]
         [DataRow(StorageAuthenticationType.IdentityBased, true)]
+        [Ignore("Waiting on IcM 279379774 to be resolved, estimated early Jan 2022")]
         public async Task RegistryManager_ImportDevices(StorageAuthenticationType storageAuthenticationType, bool isUserAssignedMsi)
         {
             // arrange
diff --git a/iothub/device/src/IotHubConnectionString.Core.cs b/iothub/device/src/IotHubConnectionString.Core.cs
index 70edd63dd0..543ea47c5f 100644
--- a/iothub/device/src/IotHubConnectionString.Core.cs
+++ b/iothub/device/src/IotHubConnectionString.Core.cs
@@ -19,11 +19,14 @@ Task<string> IAuthorizationProvider.GetPasswordAsync()
                 if (Logging.IsEnabled)
                     Logging.Enter(this, $"{nameof(IotHubConnectionString)}.{nameof(IAuthorizationProvider.GetPasswordAsync)}");
 
-                Debug.Assert(TokenRefresher != null);
+                Debug.Assert(
+                    !string.IsNullOrWhiteSpace(SharedAccessSignature)
+                        || TokenRefresher != null,
+                    "The token refresher and the shared access signature can't both be null");
 
                 return !string.IsNullOrWhiteSpace(SharedAccessSignature)
                     ? Task.FromResult(SharedAccessSignature)
-                    : TokenRefresher.GetTokenAsync(Audience);
+                    : TokenRefresher?.GetTokenAsync(Audience);
             }
             finally
             {