It's not worth it ! Don't go for it !
They charge people 20 £ for them to book you in 2 weeks earlier but I still had to wait 4 months instead of 4 months and a half and after they booked me two weeks earlier they've just stopped searching. So basically they are tricking people saying they can't find any other cancelations throughout 4 months and people end up paying 20 quids to be booked in 2 weeks earlier. Total scam ! Very dissapointed of the app tbh ! All the best ! :)