If your talking about tipping, or fimming, to increase new lower branch growth i personally would do that after the plant shows maturity. Alternative branching.
I no longer tip or fimm (prune)to create bushier plants as i train mine horizontally and let the lower growth keep up with the main cola.
If your talking about pruning off fan leaves, i suggest not, as they are required during the latter stages of flowering, and will die when no longer required.
Tie them out the way if they concern you
