Sept 28th and 30th were quite perculiar, market-internal-metric-wise.
The behaviour on the 28th has only happened 3 times since 1980.
The 30th, a lot more, but both have average +ve outcomes after 20-30 trading sessions.
I have plotted/charted all the outcomes, and posted on twitter.
[NB most of the metrics I use, can be found on this TradingView website]