I just receive an email saying my NBN installation date is 16/10/2017.
My last ADSL bill shows the current period is 16/09/2017 to 15/10/2017.
Just want ask if I will be charged one more adsl bill for the period 16/10/2017 to 15/11/2017?
Yes, you'll still be charged for your ADSL renewal 7 days in advance, on 9 October. However, when your NBN is installed, you will recieve a credit on your account for the unused ADSL billing cycle.
This credit will be offset against whatever NBN charges you will incur upon installation (e.g. plan change fee if applicable / your first monthly NBN fee - whatever it may be in your case).