Telstra bring your own plans clearance

Product Name: Telstra bring your own plans clearance
iTWire - Telstra's new Pre-Paid Plus plans very competitive at $40 and $50 clearance, Telstra Reveal Revamped Phone Plans - clearance, iTWire - Telstra expands its unlimited plans, includes new $199 plan with unlimited full speed data 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.