submission of Surety Bond is a procedural requirment of CSA and not MoC, therefore, the bond is required @ time of joining CSA. there is no problem if u send it right now or submitt it while joining CSA, what matters is that if u send it now (through mail or delivery by hand) it might get lost and u have to re-submitt that. I discussed the same with Ahmed Fasih SO (Admin) MOC he advised me to forward a copy of acceptence letter alongwith a copy of surety bond to CSA and submitt orignal @ time of joining.