It’s not a contract. You can cancel whenever you want.
Only pay month to month and you don’t have to keep the membership for the full 12 months. If you cancel you’ll just lose the discount and you won’t be charged further payments.
Yes if you cancel fully on month nine then you only pay nine months.
When cancelling make sure you go through all the screen steps (where there is either 4 or 5 steps).
After fully cancelling the Sports Membership you should also get an email confirmation from NOW.
If you have also taken the free one month Boost Membership with the offer, then cancel Boost before the first due payment date if you don't want Boost.