Once you purchase an iPhone 15 Pro 256GB and you trade in a paid off and in good condition iPhone 11 Pro, it is eligible for $350 promotion trade in credit. This how it will work, your device estimated trade in value is $120 it will be applied on the account once the device is received on the warehouse and the remaining credit of $230will be applied on the new device installment and that is $9.58 per month for 24 months. so instead of paying $45.84on the iPhone 15 Pro, you will just pay $36.26 per month for 24 months.