There has been no "traditional" to the scheduling of the NARRCOFFS. Started competing in them 25 years ago, have missed a few along the way, but have been to many. Way back, it was Practice Fri. AM, Qualify Fri. PM, race once on Sat. Then it changed to both sessions on Fri. we're Practice/Qualify, race once on Sat. Last year it was Qualify Fri. AM....time set the grid for the Fri. PM "Qualifying Sprint"...position set the grid for the Sat. AM "Qualifying Race". Grid for the big "Feature" was set by best lap time from any of those 3 sessions. I remember because I purposely started at the back all 3 times to stay out of the craziness.

It's evolving...unless you're a creationist, then it was planned ~8000 years ago.