The stock to flow model seems to be one of the best predictions of Bitcoins price.
The standard deviation bands are supposed to show situations in which Bitcoin is significantly over- or under-bought.
In true TradingView spirit, the author of this script has published it open-source, so traders can understand and verify it. Cheers to the author! You may use it for free, but reuse of this code in a publication is governed by House Rules. You can favorite it to use it on a chart.