When I had my induction course, I think I did a simple 10 question paper exam. For example, it showed a pictures of different earthing arrangements and you had to put down which was which.
It's not even a course. I did mine when the manager came round to my house. It took half an hour maybe and most of that was spent going through paperwork making sure you understood what was required. I didn't go to Leeds to pick up my van as there was one more local but I did go to Leeds to pick up my PPE, and work tops etc. and meet the Senior manager but it was very informal.
They are short of Sparks, especially in the South but basically, if the Area Manager says yes, then head office aren't going to argue. If you can wire up different boilers then there's no reason why you won't get the job. Even if you struggle with them, get a copy of the Honeywell Wiring guide (version 16) and that has every heating system that you are going to be doing. As I've said before, you'll be doing mainly combi and Y plans. Very few S plans.
Most of the boilers are Worcester Bosch with Vaillant, Ideal Logic and the odd Baxi thrown into the mix. Controls are normally Honeywell but it depends what the Surveyor recommends. Most stats are wireless and you just have to go through the controls with the client at the end of the job.
Hope this helps.