Take all points in the RSI graph where the RSI drops below being oversold (Os), or rises above being overbought (Ob). Take the last point in each of the local oversold or overbought series, and map each last Os point to the next last Ob point.
For ETH, the method above has 100% predicted the best tops and bottoms ever available. The best feature of these RSI gains is that they have never broken their trend line (historically), so it's highly likely we won't see RSI below 50 before December.
This makes a huge drop very unlikely, and net positive gains in that timeline very likely.