You are effectively getting a 12 month price guarantee @lmj66060 so the process is
When you reach month 11 of your Home Essentials plan, we’ll contact you to let you know that you’re nearing the end of your 12 month price guarantee and inform you we’ll run another eligibility check on your plan’s 12 month anniversary. If you are still eligible then we’ll notify you and inform you that we’ll renew your plan for another 12 months unless you contact us to tell us you’d like your service to end. Following each renewal, you’ll be moved to the equivalent latest Home Essentials package we offer at that time and the monthly price of your package will change to the price of that equivalent latest Home Essentials package as well.
As @rbz5416 highlighted any additional optional addons to the plan like TV would be subjected to annual price increases.
