* June WCS last seen at $22.75/bbl under WTI
* June synthetic at $0.65/bbl discount to WTI
CALGARY, Alberta, May 7 (Reuters) - Canadian oil pricesedged higher on Tuesday on talk BP Plc plans to begin thestart-up of an upgraded crude distillation unit at its 405,000barrel-per-day Whiting, Indiana, refinery at the end of May.
Western Canada Select heavy blend for June delivery lasttraded at $22.75 per barrel below the West Texas Intermediatebenchmark, according to Shorcan Energy Brokers.
That compares with a settlement price on Monday of $24 perbarrel under WTI.
Light synthetic crude from the oil sands last traded at adiscount of $0.65 per barrel under WTI, down from a settlementprice on Monday of $0.8 below the benchmark.
BP's upgraded crude distillation unit is intended to liftthe refinery's capacity to run Canadian crude oil to 350,000 bpdfrom 80,000 bpd, and would give a significant boost to demand.
One source familiar with refinery operations said BP wouldlike to see the crude unit in operation this month.