Telstra NBN $1 First Month on NBN 50, NBN 100 and NBN 250

Received this via text message from Telstra.

Get first month for free on NBN 50, NBN 100 and NBN 250. 24 months plans only. That's up to $139 off.

Get your first month for just $1 on selected home internet plans. Offer ends 19 December.

For new services. If you leave within 24 months, simply return your modem or pay a $200 non-return fee.