Split Rows based on Condition

Hi,

Try this code

let
    Source = Excel.CurrentWorkbook(){[Name="Data"]}[Content],
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Start Date", type datetime}, {"End Date", type datetime}, {"Contract Length", type text}}),
    #"Duplicated Column" = Table.DuplicateColumn(#"Changed Type", "Contract Length", "Contract Length - Copy"),
    #"Added Index" = Table.AddIndexColumn(#"Duplicated Column", "Index", 1, 1),
    #"Reordered Columns" = Table.ReorderColumns(#"Added Index",{"Index", "Start Date", "End Date", "Contract Length", "Contract Length - Copy"}),
    #"Split Column by Delimiter" = Table.SplitColumn(#"Reordered Columns", "Contract Length - Copy", Splitter.SplitTextByDelimiter(" ", QuoteStyle.Csv), {"Contract Length - Copy.1", "Contract Length - Copy.2"}),
    #"Changed Type1" = Table.TransformColumnTypes(#"Split Column by Delimiter",{{"Contract Length - Copy.1", Int64.Type}, {"Contract Length - Copy.2", type text}}),
    #"Removed Columns" = Table.RemoveColumns(#"Changed Type1",{"Contract Length - Copy.2"}),
    #"Added Custom" = Table.AddColumn(#"Removed Columns", "Custom", each if Number.Mod([#"Contract Length - Copy.1"],12) <> 0 then Number.IntegerDivide([#"Contract Length - Copy.1"], 12)+1 else if [#"Contract Length - Copy.1"]=12 then 2 else Number.IntegerDivide([#"Contract Length - Copy.1"], 12)),
    #"Added Custom1" = Table.AddColumn(#"Added Custom", "Custom.1", each {Number.From(1)..Number.From([Custom])}),
    #"Expanded Custom.1" = Table.ExpandListColumn(#"Added Custom1", "Custom.1"),
    #"Removed Columns1" = Table.RemoveColumns(#"Expanded Custom.1",{"Custom", "Custom.1"}),
    Partition = Table.Group(#"Removed Columns1", {"Index"}, {{"Partition", each Table.AddIndexColumn(_, "Index1",1,1), type table}}),
    #"Expanded Partition" = Table.ExpandTableColumn(Partition, "Partition", {"Start Date", "End Date", "Contract Length", "Contract Length - Copy.1", "Index1"}, {"Start Date", "End Date", "Contract Length", "Contract Length - Copy.1", "Index1"}),
    #"Added Custom2" = Table.AddColumn(#"Expanded Partition", "Advance start date by", each if [#"Contract Length - Copy.1"] < 12 then 0 else 12 *([Index1]-1)),

    #"Added Custom3" = Table.AddColumn(#"Added Custom2", "Custom", each if [#"Contract Length - Copy.1"]=12 then Date.AddMonths([Start Date],0) else Date.AddMonths([Start Date],[Advance start date by])),
    #"Reordered Columns1" = Table.ReorderColumns(#"Added Custom3",{"Index", "Start Date", "Custom", "End Date", "Contract Length", "Contract Length - Copy.1", "Index1", "Advance start date by"}),
    #"Added Custom4" = Table.AddColumn(#"Reordered Columns1", "Advance end date by", each if [#"Contract Length - Copy.1"]-[Advance start date by] > 12 then 12 else [#"Contract Length - Copy.1"]-[Advance start date by]),
    #"Added Custom5" = Table.AddColumn(#"Added Custom4", "Custom.1", each Date.AddDays(Date.AddMonths([Custom],[Advance end date by]),-1)),
    #"Reordered Columns2" = Table.ReorderColumns(#"Added Custom5",{"Index", "Start Date", "Custom", "Custom.1", "End Date", "Contract Length", "Contract Length - Copy.1", "Index1", "Advance start date by", "Advance end date by"}),
    #"Removed Columns2" = Table.RemoveColumns(#"Reordered Columns2",{"Start Date", "End Date", "Contract Length - Copy.1", "Index1", "Advance start date by", "Advance end date by"}),
    #"Renamed Columns" = Table.RenameColumns(#"Removed Columns2",{{"Custom", "Start Date"}, {"Custom.1", "End Date"}}),
    #"Changed Type with Locale" = Table.TransformColumnTypes(#"Renamed Columns", {{"Start Date", type date}, {"End Date", type date}}, "en-IN"),
    #"Removed Columns3" = Table.RemoveColumns(#"Changed Type with Locale",{"Index"})
in
    #"Removed Columns3"