Lane markings causing confusion, could lead to accident.

Coming down the slip road to Tesco from town the LH lane indicates left turn to 'Retail Park'., the centre lane is straight on the Frenchay. The trouble is there is no lane identifying LH turn is also to Horfield. I see often drivers in the middle lane then turning left to go to Horfield (from previous signage as was), but also those in LH lane turning left to Horfield. Thus we see two lanes trying to merge into one just at the turning. Would be better to make it clear if middle is straight on only, or if LH turn is permitted, and then LH turn marked for Retail / Horfield; or make centre lane straight on and Horfield. Either way, it is not clear and causes confusion.