The rally from 26.03 looks like a leading diagonal. Crude went down from 51.64 in 3 waves (wave A) followed by a 3-wave rally back slightly beyond the start of wave A in a B-wave.
This suggests a flat in progress, so I believe 51.91 is the top of wave B and from here 5 waves down can be expected in a wave C. On the faster charts the first 5 minor waves seem to be almost complete (larger wave 1).
