Telstra / NBN difficulties, page-3

This may help

How to use it
To turn on Call Forward Immediate for all incoming calls:
2 1 Phone number #
To turn off Call Forward Immediate for all incoming calls:
# 2 1 #
Call Forward Immediate is ready to use on your phone now.
It overrides all other Telstra Voice features except Call Forward
Selected Callers. Your standard call charges apply for the calls
you forward.