Is there any way of querying Telstra re this number?

I get the same - hang up on answer plus out of service message if you call back. Blocked this number but now the same thing is happening with this number (02) 8705 3280 which is the 'one up' from (02) 8705 3279.

I blocked this number on my phone. Kept getting calls day and night.

They called between 5-7pm and when I answered. They hung up.

Experienced the same issue, smells dodgy

Missed call, call back to number doesn't exist.. blocked now.

me too, got call from this number,
must be some one/company/gov(perhaps) we don't know...but i don't think this was coincidence, and indeed, join my blocked caller list too.

same got a call from this number and when i call back mentions invalid number

calls from this number in afternoon & early evening , when you answer nobody speaks
when my wife says hello they hang up quickly
redial the number and you get the message "the number is not connected"

Received a few calls from (02) 8705 3279 on my mobile and they simply hung up.
Another number on my blocked caller list.

They try to call me and there is nobody there when I call back