Enter play mode from editor script after baking is complete

Hello,

We have an application we are developing where we like to enter play mode from an editor script once the scene is opened. I have created an editor script that is contained in the folder Assets/Editor directory that does the following:

 using UnityEditor;
 using UnityEngine;

 [InitializeOnLoad]
 public class MyEditorScriptExisting
 {
     static MyEditorScriptExisting()
     {    
         EditorApplication.ExecuteMenuItem("Edit/Play");
     }
 }

It is successfully called and ran, however we get this error when trying to run the function ExecuteMenuItem:

 ExecuteMenuItem failed because there is no menu named 'Edit/Play'
 UnityEditor.EditorApplication:ExecuteMenuItem(String)

Is there anyway around this, or is there something we are doing incorrectly? We'd like to run the application on startup and also like for it to wait until the baking is complete before entering play mode. I followed this thread here Start/Stop Playmode from editor script which helped in getting a script to execute in edit mode, but whenever I try and run the ExecuteMenuItem function it throws this error. Any help would be greatly appreciated.

Thanks!