S2 is a selfing from my keeper s1. More times u self the more homogeneous they are. There's gonna be some variation that's why selection is important but the s2 will be more like the s1 mom used.. But good or bad recessive traits can still be hiding with variation occurring among sibling seeds so the selection process must be repeated with adequate s1 seed to achieve more homogeneous s2,s3,s4 seeds. Yo must still do selections in any of these if u wish to make stable copys of the mom. . To much inbreeding can cause issues we dont want. I would never go passed s3. At this point its an IBL. Most of the plants should be identical. If I use that selfed pollen on a different clone then I have a female hybrid. I prefer making female hybrids. It adds back genetics diversity. It took 5 years to find a better fem Hybrid version of Sdubb.
S1 will have more variation then a s2. Stress tested s2’s of excellent mothers are breeding gold as they are homozygous for all traits seen in the s1 individual selection.