Suggestion no.1 - post in Private flying, not professional training. They will have a better idea of PPL schools.
Suggestion no. 2 - only ever pay as you go. Do not pay in advance. You tell Cabair that you will take your business elsewhere (and I'm sure there are equally as good/bad places to learn) if they won't let you fly weekends and pay for only what you fly at the end of the lesson.
Cheers
Whirls