I used to think there was a magic number, like “10 lessons and you’re ready,” but in my experience it varies a lot. Most learners I’ve seen fall somewhere in the range of a couple dozen hours of proper practice, but that number can rise or drop depending on how often you drive, how quickly you pick up routines, and whether you practise between lessons. When I learned, what slowed me down wasn’t steering or gears, it was decision-making at junctions. Once I fixed that, my progress suddenly felt much faster.
Here’s the practical way I’d approach it: after every lesson, I write down three things, one thing I did well, one thing that felt shaky, and one “next time” target. After 6 to 8 lessons, patterns show up. If you’re still repeating the same mistake, you may need more time. If new topics are sticking quickly, you’re likely close to test standard.
If you’re exploring this subject Imperial Driving Academy offers some valuable information.
Just to add, I’d book the test only when you can drive reliably on an “average day,” not just on your best day, because the test is basically a check of consistency.