Alyssa (my partner) completed this route on 1/25/25 from the South Side (Wailua/Keahua Arboretum) as part of a longer 30 mile training run starting at 8:12am. We flew over from home on Oahu for her to do her long training run on this route. She started at the Moalepe Trailhead, connecting that trail to Kuilau Ridge Trail before reaching the Keahua Arboretum area and the short section of forest road to the Powerline Trailhead (this part of the effort took 47:09, after which point she began the FKT route. The effort was self-supported as hydration/nutrition was staged in a car at the North (Princeville) Trailhead-- however, this was the only refueling she did for the entire run. She made it from the South trailhead to the North in 1:51:13, took a couple minutes to swap a bottle and grab additional nutrtion, and turned around. It took just over 2 hours to return to the South trailhead. Her elapsed time for the RT effort on the FKT route is 3:53:52. It then took her an elapsed 54:57 to run back on Kuilau Ridge/Moalepe Trails and to complete an extra quarter mile on the road to complete her run for the day in 5:35:58.
There is no functional difference in starting from the North vs the South, and it would be prudent to remove "Princeville Start" from the title. Local runners would be more likely to start from the south vs visitors starting at North (near resort area). Both directions should be considered standard to encourage participation on this route!