Problem with paying large sums upfront is that it’s not used to pay for your training.
It’s used to pay the monthly fuel bill, utilities, rent, airplane maintenance, those parts they planned on ordering etc etc etc.
Yes you may have a £5000 credit on your account but the physical money is gone.
Now it’s important to know for every business large or small to know that you can pay your flying bills.
A good compromise is to pay ahead the day of your actual lesson(s).
When you get to the crosscountry stage you can easily burn through £400-500 in a single day.
Same when you do 2 or 3 training flights on that nice weekend day.
Show up, deposit £300-£500 in your account and get on with flying.