Usually networks have been asking for 24 or even 36 month contracts to get the discount offer. In this case it makes the iPhone 13 cheaper than the 13 Mini and if your trading in a iPhone via the Vodafone's tradeup service you may save even more. I recommend the 12 month offer myself and you get the $400 off pro-rata each month's repayments
Reasons to start thinking of Vodafone/TPG Group is they have done a deal & will soon have a roaming on Telstra for awesome coverage, you get wifi-calling and it might be an idea to lock in a good plan now as Telstra has gone to indexing plans to CPI!
TELSTRA DAY SALE INFO ON IPHONE13 SERIES So you can compare deals: https://www.ozbargain.com.au/node/710581
NOTE: Vodafones offer is $50 better value than Telstra's and the plans are better value too, so Vodafone for the win!
So regardless the plan u got $400 off the top for staying 12 month?