This is a tough question: Stanford's famous What Matters Most essay is so personal, it's hard to imagine writing about something ELSE only a few months later. It's also hard to write a reapplicant essay showing growth after such a short period of time. This is one of those cases where I would recommend a review by a professional consultant such as our staff here at SBC: normally I would say "assume that everything needs to be redone from scratch," but the fact that you got an interview, which is quite rare in itself, indicates that you put together a terrific application last time. I would want to analyze your essays in depth to see whether they are delivering maximum value for you, and what if anything needs to be tweaked.

Sorry I can't be more specific about your approach here, but it's a unique case and general rules don't apply. I would need to review the materials before weighing in.

Good luck!