Honestly (and major apologies to all English gurus and purists out here), but I suggest writing and memorising some adaptable context pieces. 'Writer's block' during the English exam is an absolute disaster if you have no back-up plan, it can pull your ATAR down from 80 to 70 in a matter of minutes.
I think if you can write 3 or 4 adaptable pieces (by adaptable, I mean you can alter and tweak them to fit a specific prompt) on three different areas of your context and then memorise said pieces, that's a good back-up plan. Worst thing that could happen is that your piece isn't 100% relevant and you scrape a 6/10 or something, that's still way better than handing in a context essay that's blank and soaked in your tears

(I did this, and I'm far from competent in VCE English, worked for me!)