The present disclosure relates to a fiber optic telecommunications cable assembly including a main fiber optic cable and a tether cable that branches from the main fiber optic cable at a breakout location. The breakout location includes a breakout block mounted to the main fiber optic cable, a tether retention block mounted to the main fiber optic cable, and a sleeve positioned outside the main fiber optic cable that extends from the breakout block to the tether retention block. An optical fiber structure extends from the main fiber optic cable, through the breakout block, through the sleeve and through the tether retention block to the tether cable. The fiber optic telecommunications cable assembly also includes a tensile reinforcing structure that extends from the breakout block to the retention block for preventing a spacing between the breakout block and the retention block from exceeding a predetermined amount. The tensile reinforcing structure is positioned outside the main fiber optic cable and has portions anchored to the breakout block and the retention block. The fiber optic telecommunications cable assembly further includes an over-mold that covers the breakout block, the sleeve, the retention block, the tensile reinforcing structure and at least a portion of the main fiber optic cable.