A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data
Most likely, the very first time you created the query there were 10 columns. PQ created M code like this:
#"Split Column by Delimiter" = Table.SplitColumn(Source, "Column1", Splitter.SplitTextByDelimiter("/", QuoteStyle.Csv)**, {"Column1.1", "Column1.2", "Column1.3", "Column1.4", "Column1.5", "Column1.6", "Column1.7", "Column1.8", "Column1.9", "Column1.10"}**)
Remove everting that is red/bolded and next time PQ will split the column based on whatever number of delimiters it finds.