When you go to My Account > Bills & Payments what does it show under recent and future payments ?
Normally the £30 Super Fibre charge occurs on your live activation date of the NowTV Broadband service being activated.
When my sister signed up to NowTV Broadband they didn't take any money on the live activation date and rolled over the full payment to the next following month for some unknown reason, though my sister was aware of it by viewing the Bills & Payments Section of her account.
Also when you signed up to Super Fibre did you select the saver option with a 12 month contract commitment (where the non saver option is a no contract service where you can leave at anytime which involves a fee of £60).
Maybe give the NowTV Broadband Team a call, where you will find their telephone number under My Account > Orders & Appointments (click the down arrow below your live date to see the telephone number to phone).