Telstra mobile plan small $50 Clearance

Product Name: Telstra mobile plan small $50 Clearance
Is this even legal? Telstra automatically upgrading me to a more expensive plan without asking. Currently paying $39 month-to-month ($10 monthly discount at signup) for 15gb. : r/AusFinance Clearance, Telstra Reveal Revamped Phone Plans - Clearance, iTWire - Telstra's new Pre-Paid Plus plans very competitive at $40 and $50 Clearance, Is this even legal? Telstra automatically upgrading me to a more expensive plan without asking. Currently paying $39 month-to-month ($10 monthly discount at signup) for 15gb. : r/AusFinance Clearance, Telstra Upfront plans explained: What's the difference? | Reviews.org Clearance.