When a trend retraces or pulls back it begins right after the max volume occurred on the advance. At the end of any retrace or pullback you will see that the lowest volume was attained or reached.
Within a trend, the price moves in the trend direction as volume increases, and price retraces within the trend as volume decreases
when the volume peaks on the resumption, then the price MUST make a complete TRAVERSE to the opposite side of the trend's channel. If price does not make it, then you have just completed the final traverse of the trend. Thie end of the resumption is, in fact the very beginning of the new trendline of the next trend.
