Welcome to TPG Community!
Our sincerest apologies for what happened as no provider would wish to cause inconvenience to their customers. I can only imagine how frustrating your experience has been.
We understand that you've raised this case on our Facebook page and the case was escalated to our Service delivery team.
The schedule that was given to you was the earliest that your case manager can get from NBN as they need to consider the availability of their technician. We weren't able to advise you that the initial schedule was canceled since we received the update from NBN Co on the same day as well.
A case manager is monitoring your account and will provide further updates once available.