For the 24h projections to be of any use you need them to land in the same session cycle as the actual high or low, or if there is a change in the dominant cycle, then the change in 24h cycle translation (and therefore also the projection accuracy) should be explained by this change.
This morning I started working on improving this projection accuracy. I thought about writing an indicator in order to extract and forecast the cycles, but it would take too long. Therefore I decided to do it on paper first. Here is a screen shot of the first draft:
There are some quite big differences, so I am going to go back and revisit the data and check the accuracy, and also see if I can come up with a more consistent set of rules.