April RBOB prices are higher to start this morning and seem to be drafting support from higher crude oil pricing. Some traders noted concern after gasoline futures appeared to overlook weakness in the cash markets, which were lower on a change in contract periods from February to March. There were also reports earlier this morning from Petrobras indicating that the company would not increase their gasoline prices in the face of higher world oil markets but that they did expect high levels of market volatility for months ahead.