weekly charts Weekly charts had to finish to send clear signal. Now if spx or oil weekly charts look bad then wave 2 rally in jeopardy.
Bollinger In monthly spx wave 1 as you say markets become oversold and wave 2 tries return to MID BB CL which is actual true prices spx (2032) (will change a bit).
Then wave 3 is straight down and you can no longer use bollinger bands.
As the bear ends spx monthly hits RSI < 30 and the end of bear confirmation is return mid BB CL in New wave 1 uptrend.