I got my Paramount subscription details email today.
PSA: I have an existing account but the instructions for existing account holders didn’t work (I didn’t have a “Subscription & Billing” section. I was able to follow the process for new account holders (logged in with my existing account) and that worked fine.
Tip: Choose the monthly billing option. This kicks in at the end of the 12 month promo subscription. That way if you haven’t got your promo code in time next season and forget to cancel, the worst case is you pay for a single month, rather that a whole year.
Note that you need to enter credit card details but they would only be used at auto renewal after the 12 months.