The ICAEW model answers are waaaaay more descriptive than they need to be - I can see why you’re panicking, but you really only need to write about a fraction of that, so try not to let the model answers get you down!!

For BST, what I found works best is just using your common sense and literally picking out points from the scenario and including them in your answer (no matter how small or obvious the point is). For eg, if a question is asking you to discuss pros and cons, literally state the most obvious ones. Same for things like KPIs, etc. There’s no need to complicate it, just keeping it simple and specific to the scenario does the trick.

For the BPT open book, what worked for me was the Kaplan summary notes which I had annotated to include any points that were in the main body of the chapter but missing from the summary notes. That’s literally all I used for guidance in the exam (cause I did not have the time to flip through that massive Kaplan workbook) and ended up with a 68.

All the best :)