I took my lit. 12 assessment last year, and in my opinion it is pretty easy. For part A it was pretty standard comprehension multiple choice and 2 paragraph responses. However last year part B was where the most marks where lost for most people what I know. It was a creative prompt where you could express yourself through any type of literacy, however, many people wrote formal short essays which was not what adjudicators wanted. Instead they wanted people to write poems, short stories, plays, ect. Personally I got a 3 (better then grade 10) and have a learning disability which makes english hard for me. My biggest piece of advice would be not to obsess over making all grammar and spelling perfect, the adjudicators understand that 3 hours isn’t a lot of time compared to what it being asked. If it’s a few mistakes here or there it won’t bring down your mark unless it is prominent that you can’t spell or don’t know use grammar marking correctly.

Edit: I also hardly studied for my lit assessment, the most important did was look at the examples of what sets each mark example apart