Your status updates can only be seen by someone if you have their phone number in your phone’s address book and they have your phone number in their phone’s address book. You can choose to share your status updates with all your contacts or selected contacts only. By default, your status updates are shared with all your contacts.
But sometimes we can see that some unsaved numbers view our Status Updates.
Reason: If someone view your status updates by unsaved numbers, reason is that the user change their WhatsApp number before view your status and immediately saw your status updates. Old number is already in your contact, the user can view the existing Status of all contacts.