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This depends on the type of nbn™ service being connected and whether there has been nbn™ equipment previously connected. TPG will advise you in advance if the nbn™ technician requires access into your premises.
To better understand the status of the NBN installation send me your account details (Username/Customer ID together with the address on file).
In case you need a reference: How do I private message (PM) in the community
NBN installation in Sydney to copper telephone wire. What does the technician install inside my townhouse? What does the technician install outside my townhouse?