Ghost Webhook Integration

Hi everyone! I’m integrating Webhook into my Ghost. This webhook is connected to the workflow in n8n and listens to the Member Updated event.
I noticed that each time a member changes name or email in Ghost, I get this JSON:

[
  {
    "body": {
       "member": {
          "current": {
             "id": "123",
             "uuid": "123",
             "email": "bob@example.com",
             "name": "Bob",
             "note": null,
             "subscribed": false,
             "created_at": "2023-06-04T14:25:16.000Z",
             "updated_at": "2024-06-04T14:27:31.000Z",
             "subscriptions": [
              ],
             "status": "paid",
             "tiers": 
                [
                   {
                      "id": "321",
                      "name":  "Test",
                      "slug": "test-2",
                      "active": true,
                      "welcome_page_url":  null,
                       "visibility":  "public",
                       "trial_days": 0,
                       "description": "....",
                       "type": "paid",
                       ....
                 }
             ],
             ....
            "previous": {
                "updated_at": "2024-06-04T14:26:25.000Z",
                "name": "Bill"
            }
         }
      },
    "webhookUrl": "webhook_url",
   "executionMode": "production"
  }
]

As you can see, there is a key called ‘previous’, which should show the changes, which have been made in this request.

The thing is that when a member updates his tier, these changes don’t show in the ‘previous’ key.
For example, if a user changes tier from ‘Test’ to ‘Test1’, I expect the ‘previous’ value to be like:

[
  {
    "body": {
       ...
       "previous": {
                "updated_at": "2024-06-04T14:26:25.000Z",
                "tiers": 
                    [
                       {
                          "name":  "Test",
                       }
                    ]         
          }
       ...
     }
]

But instead of this, I’m getting an empty value for ‘previous’.

Can someone, please, explain to me, how it works? Perhaps, there are some alternatives, or should I use a different event for Webhook?