while you are on the subject of candles which span some arbitrary but regular span of time, I recommend you become familiar with the subject of candlestick addition
In particular I find bookends a most useful pattern, because when you add them together they are a simple dragonfly doji, which has good reliability.
and on the subject of the monthly, it does have peculiar problems in that many months have strange numbers of trading days due to the length of the month and the presence of public holidays. Shanghai during new year being a good example.
