I run starters until I see it becoming
significantly lighter, then give them another 6-12 hours before crashing it.
That's not a Saccharomyces strain!
It's a Lachancea strain/isolate, she behaves
very differently.
Most of your answers and directions to proper use can be found here:
https://www.lallemandbrewing.com/wp-content/uploads/2021/10/LAL-bestpractices-Philly_Sour-ENG-A4.pdf
Here's an excerpt that may answer some of your questions:
Attenuation and ABV calculations
Since WildBrew Philly Sour™ produces both lactic acid and alcohol during fermentation, there are implications for determining the attenuation of the fermentation. When lactic acid is produced, there is no CO2 released and therefore no loss of mass and no change in density. Therefore, for WildBrew Philly Sour™ fermentations the FG will be higher, the change in density will be lower and the apparent attenuation determined by measuring density will be lower even if the same amount of sugar is metabolized (real attenuation is the same). The amount of lactic acid is equal to the increase in FG of the beer compared to a similar standard brewing strain.
We also have our main Philly Sour thread here on HBT:
https://www.homebrewtalk.com/thread...y-sour-feedback-or-experience-to-share.682096
IIRC, making starters with that strain or repitching can produce unexpected results as to fermentation and souring levels.