First Ultra/FKT Attempt: What am I missing?

I’m planning for an unsupported Fastest Known Time attempt. The run will be in October and is ~60km, primarily road/sidewalk. I’m planning on doing it at night to minimize traffic slowdowns or stops. I need to maintain a pace that’s slightly faster than my easy pace, but slower than my MP.

I’ve run multiple marathons, but never an ultra. My last marathon in November 2024 was a BQ at ~3 h15m. I’m ramping up my weekly mileage as part of my current plan – sitting at around 70k/week - and will peak at 100k/week in late September. My longest planned run is 40k and I have multiple back-to-back long runs in the schedule.

As the run is unsupported, I’ll be carrying all my nutrition and water. Hopefully, the temps are good. I’ll be using a mix of pure maple syrup, Saltstix, and Gu with caffeine. I’ll also have 3 litres of water (vest with bladder and two softflasks). I’ll need a light for a portion of the run – and I have a Petzl Bindi, which I hope will do the job. I’ll be wearing my usual gear – nothing new. For shoes, my Boston 12s are the likely contender.

The route is straightforward (no navigational issues) with less than 300m of elevation gain in the front half, and the second half is largely downhill.

With all that said – I feel like I’m missing something. The pace-math works out, I know the route, I’ve got my gear and yet I have a nagging feeling.