You should wait atleast 3 days after transplanting but preferabally longer like a week or two before entering the flowering phase,there will be a shock to the plant from transplanting,the shock is normal but the shock will stunt growth if the plant enters flowering while its still in shock from the transplant.I meant, transplanting in the last pot (a bigger one) and switching to 12/12 right after... Or should I wait before switching light cycle? the time for the plant to make new roots etc... if yes, how long?