NO unlimitted cancelations, only 1
They claim the paid subscription provides "UNLIMITED cancellations for UNLIMITED changes until your next test". However after the first booking it stops finding anything. Well they found you one slot and don't have to return money anymore. I saw tests available in the mobile app and on gov.uk itself, but somehow autobooking here didn't work. My advice: use other websites and apps. Or at least set your time window as early as possible - no earlier rebookings here.