I have a 30k trail event in 3 weeks time. It’s a fast event (except for the sandy beaches) south of Sydney. I have been on reduced carbs for a month, and on a full on Keto diet for a week (feeling good). I train at a low intensity, but can run fast in events (at a cost latter). This even is one of 2 Alpha events on my annual calendar where I really put the hammer down. So I am keen to get a good time in this event, rather than just go along for the ride.
My questions for this are:
1/ If I was going to take on board some carb fuels for the event (it will mostly be anaerobic), then what fuels should I consider if I have been mostly keto for the preceeding month ?
2/ Pre event fuelling, should I up the carbs the night before, or early on the day before the event ? If so again, what sort, complex or simple carbs. I would be inclined to do complex.
I will try to do some 20k runs before the event with some fuel experiments, but as there will be only 2-3 of those I need to narrow down the options 
For a longer event, eg: the UTA 50k then I would probably lean more towards keto like fuels with some carbs as a back up. The UTA will be in May 2022, so there will be more time to adapt and experiment.
Note - trail running is not as steady state as road running, so there will be anerobic section on the uphills /.
PS: I dont eat gels, really dislike them. In the past if I need carbs in a fast event, then I used " Fruit Salad Soft Jellies" a lolly from Woolies or Coles, mostly sugar and glucose. Once I start eating the carbs, then I pop them one at a time like clockwork every 15-20min. In very long events 50-100k, I like slabs of cheese in a SD baguette or chibatta, soaked with olive oil (been doing that long before I even heard of Keto).
I have perused the web for ideas and have listened to many Zach Bitter podcasts, etc. But most of the carb suggestions are delivered in a liquid form. I have evolved my event nutrition to the point where I drink mineral water/electrolyte and eat carbs seperately, that way I can better manage the body demands & only have the calories when I need them.
Thanks 
a brilliant race report. I can fully understand how good it is to beat your nemesis and win your age category. Top work!! It will be interesting see the evolution of your nutrition strategy.
in my age group too 
Long uphill, oh my…