Does adding another house unit change the service available at the first house

Apr 22, 2015
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4,510
I am trying to change my isp to Optus Australia and I was checking available plans at my address (1/20 hidden road) and there was adsl2+ available but when I enter the previous address of my house which is 20 hidden road the available service is cable so does building another unit change the available service at the first unit? Thanks for helping :D
 
Apr 22, 2015
17
0
4,510

but it doesn't make sense since the existing infrastructure have not changed. So why does the available service change?