Scrip for Red Dog Reversal

The only ambiguity in your specification is "...and price trades back down through that price...". There are two ways this can be possible. To begin, both involve checking if the high of current bar is higher than previous bar. Stage two of this element is where we have options. We can check if the bar also closed below that level (trades back down through that price). Or we can check if the low of that bar is less than that level (trades back down through that price). Both of these scenarios will fit your specification.

So what I have provided here is the first of those two options:

input numberOfBars = 2;
def upBar = close > open;
def triggerBar = Lowest(upBar[1], numberOfBars) > 0 and high > high[1] and close < high[1];