Driving lessons - how many?

[Anon751117000]

My 17yo has been getting driving lessons. I have been paying for them in blocks of 5 lessons (2 hours per lesson). So far, I have paid for 5 blocks of lessons which now in total as cost me £1800. Every time he comes to the end of a block, the instructor asks me for another payment. I keep asking him how many lessons are needed and was originally told at least 40 hours but you just pay for lessons until he passes his test!
I messaged him today to ask how many more lessons are needed and his response "he needs to pass his theory then book his text, lessons taken until he passes". I then explained its a 5 month waiting list for practicals so no way am I just gonna keep paying for lessons. he said he could get a cancellation if he's ready.
Does this sound right? I feel like he's taking the pi**. I do take my son out occasionally but I'm a nervous passenger so it never ends well.
He did fail his theory so has it booked in again for early June.
Maybe this is normal and he's just not picked it up very well - I'd be interested to hear other's experiences. I cannot afford any more.

EDIT: I've have just googled it and read that they should have 'on average' around 45 hours PLUS 20 hours or practice.
So, maybe its me being unreasonable. Yikes, I'm gonna have to start taking him out more.

Just to add a driving instructor's perspective on this — the DVSA's own data says the average learner needs around 45 hours of professional lessons plus about 22 hours of private practice, but it genuinely varies a lot person to person (test centre, how often you drive between lessons, and confidence with things like roundabouts all make a difference). 40 hours quoted upfront isn't unusual at all, especially if it includes an early assessment — it's not necessarily a sign of being strung along, though it's fair to ask the instructor for a proper progress review every 5-10 hours so you can see it's moving in the right direction rather than being open-ended.
I wrote up a fuller breakdown of what actually affects the number of lessons (and questions to ask your instructor) here if it's useful: https://manchesteronedriving.co.uk/how-many-driving-lessons-do-you-need-manchester/

It’s sensible to do the theory test asap, not least because it teaches them about hazards they might come across on the road. My two took it as soon as they turned 17 and started lessons straight away.

They had 25 hours of lessons (about £1000) and a bit more than that driving with us around the test routes. Passed the practical after 6 months of driving - there’s not a lot of point stringing it out and paying £££s unless they’re struggling to get the hang of it.

My son done his theory test within a week of turning 17 then over 5 weeks had 9 hours of instructor lessons and we took him out on between - passed first time.
As soon as you get a test booked, you can look for cancellations. The first test we booked was over 4 months away, kept ch cling the cancellations and got one a week later.

Jumpimg on here as I would love to know how people get over their nerves to take their DC out! DS is learning now and I know he needs more practice but I just hate having no control over the car! He’s pretty good but I can’t relax and although I try to be calm, I actually hate every second. His Dad does take him out but is away for work a lot so it mostly falls to me.