Given the terrific paper on the Kalash, published yesterday, we finally have a clearer picture of the timing of the population processes on the Steppe.
I've discussed the "ANE" component (Lazarides paper in 2014) that is widely distributed from Europe to India back in January in this post.
By the statement I made in this post that "I strongly doubt that the R1* y-DNA haplogroup is widely correlated with "ANE" like components", I specifically mean that there is not a strong correlation of the R1b ydna hgs with this component. However, there does appear to a stronger correlation of R1a ydna hgs with the "ANE" component.
The likely reason for this split in the correlation of R1a and R1b ydna hgs is that these groups split prior to or during the last Ice Age, with R1a positioned on the Steppe 25,000 years ago, and R1b positioned somewhere in Europe 25,000 year ago.
I've thought this all along, but it's easier to argue for an Ice Age split for R1a and R1b hgs with the publication of the Kalash paper.