diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9e23e76..0f1fc82 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,12 @@
+## [2.0.2](https://github.com/kwonoj/rx-sandbox/compare/v2.0.1...v2.0.2) (2021-05-18)
+
+
+### Bug Fixes
+
+* **testmessage:** wide notificationtype<T> ([b167aff](https://github.com/kwonoj/rx-sandbox/commit/b167affd8fb9e3a63e0cc747f362e9b78f85e2a1))
+
+
+
 ## [2.0.1](https://github.com/kwonoj/rx-sandbox/compare/v2.0.0...v2.0.1) (2021-05-18)
 
 
diff --git a/package-lock.json b/package-lock.json
index c0ec2bc..3f028c0 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,6 +1,6 @@
 {
   "name": "rx-sandbox",
-  "version": "2.0.1",
+  "version": "2.0.2",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {
diff --git a/package.json b/package.json
index b9676d6..c6d7e7c 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "rx-sandbox",
-  "version": "2.0.1",
+  "version": "2.0.2",
   "description": "Marble diagram DSL based test suite for RxJS 6",
   "main": "./dist/index.js",
   "types": "./dist/index.d.ts",
diff --git a/spec/marbles/parseObservableMarble-spec.ts b/spec/marbles/parseObservableMarble-spec.ts
index acc3330..11cc43e 100644
--- a/spec/marbles/parseObservableMarble-spec.ts
+++ b/spec/marbles/parseObservableMarble-spec.ts
@@ -50,8 +50,8 @@ describe('parseObservableMarble', () => {
     const bMessages = [next(3, '3'), next(4, '4')];
 
     const customValue = {
-      a: new ColdObservable(aMessages, null as any),
-      b: new ColdObservable(bMessages, null as any),
+      a: new ColdObservable(aMessages as any, null as any),
+      b: new ColdObservable(bMessages as any, null as any),
     };
 
     const messages = parseObservableMarble(marble, customValue, null, true);
@@ -66,8 +66,8 @@ describe('parseObservableMarble', () => {
     const bMessages = [next(3, '3'), next(4, '4')];
 
     const customValue = {
-      a: new ColdObservable<string>(aMessages, null as any),
-      b: new ColdObservable<string>(bMessages, null as any),
+      a: new ColdObservable<string>(aMessages as any, null as any),
+      b: new ColdObservable<string>(bMessages as any, null as any),
     };
 
     const messages = parseObservableMarble(marble, customValue, null, false);
diff --git a/src/message/TestMessage.ts b/src/message/TestMessage.ts
index 9846ade..a96433b 100644
--- a/src/message/TestMessage.ts
+++ b/src/message/TestMessage.ts
@@ -1,13 +1,24 @@
 import { ObservableNotification } from 'rxjs';
 import { SubscriptionLog } from '../utils/coreInternalImport';
 
+/**
+ * Expanded structured type of `ObservableNotification<T>` since we can't narrow down
+ * TestMessage<T> to specific notification types, instead provide wide support
+ */
+interface NotificationType<T> {
+  kind: 'N' | 'E' | 'C';
+  value?: T;
+  error?: any;
+}
+
 /**
  * Represents interface for single metadata value emitted by HotObservable<T> or ColdObservable<T>
  *
  */
 interface TestMessage<T = string> {
   frame: number;
-  notification: ObservableNotification<T>;
+
+  notification: NotificationType<T>;
 }
 
 /**
diff --git a/src/scheduler/createTestScheduler.ts b/src/scheduler/createTestScheduler.ts
index f3a02d4..e30a2ad 100644
--- a/src/scheduler/createTestScheduler.ts
+++ b/src/scheduler/createTestScheduler.ts
@@ -49,7 +49,7 @@ const getCreateColdObservable = (state: SandboxState) => {
     const messages = Array.isArray(marbleValue)
       ? marbleValue
       : (parseObservableMarble(marbleValue, value, error, false, frameTimeFactor, maxFrame) as any);
-    const observable = new ColdObservable<T>(messages as Array<TestMessage<T | Array<TestMessage<T>>>>, scheduler);
+    const observable = new ColdObservable<T>(messages, scheduler);
     state.coldObservables.push(observable);
     return observable;
   }
@@ -75,7 +75,7 @@ const getCreateHotObservable = (state: SandboxState) => {
     const messages = Array.isArray(marbleValue)
       ? marbleValue
       : (parseObservableMarble(marbleValue, value, error, false, frameTimeFactor, maxFrame) as any);
-    const subject = new HotObservable<T>(messages as Array<TestMessage<T | Array<TestMessage<T>>>>, scheduler);
+    const subject = new HotObservable<T>(messages, scheduler);
     state.hotObservables.push(subject);
     return subject;
   }