UK Stocks-Factors to watch on Aug. 24

Aug 24 (Reuters) - Britain's FTSE 100 index is seen opening 18-20 points lower on Wednesday, or 0.3 percent lower, according to financial bookmakers. * The UK blue chip index closed up 0.6 percent at 6,868.51 points on Tuesday, helped by a rise in housebuilders after strong results from Persimmon suggested that the sector was coping with the uncertainty from Britain's vote to leave the European Union. * SABMILLER: Aberdeen Asset Management said on Tuesday it was pleased a court ha