My DS9 has a lot of sensory issues and struggled like MAD in the pool. He repeated level 1 over and over, literally for years. He FINALLY passed into level 2 at the age of 9 (I started him in lessons at 4 - I'm not joking - he just couldn't pass).
This is my son as well, though we held off on lessons the last few years because he hated them so and wasn't improving. At this point, he says he doesn't want to go swimming with friends/at camps because it's embarrassing to him that he can't swim. He also claims that it's boring exercise, though I suspect fears. I am glad that your son finally got through it! We are planning (another round of) private lessons soon.
