When to prune because of light penetration


#1

The buds that make it into the light canopy do fairly well.If I keep using same strain when should I cut the branches that don’t reach enough light?More light not an option.
For example 5 branches down are producing mature and large enough and it seems to be the same on others of same auto strain.

When should I cut the lower branches off and should the light or water leaves right below them come off also if they are catching light and staying healthy?