Change Column value from Current Value/Name

Hi AllanBerces ,

I suggest you to refer to below M Code to transform your table.

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("pdG7DsIwDAXQX0GZi5o4TkNHBBMzW9WBR5gqkPr/Aw3qkCAbW2KypRxdJ84wmNPrurHONOa831pcau7BAraxhWDGhiJWNqCI+WEOl+ctTVO6L/2uYMgzp2NemWZpB+sDcu2wMJ42ClKNYgzQxK8k3x472UQvm6AY1dMmnx3TI83zZ4dQTgOWBZXq/8kqVxmYpMrIxMkk0qTcZPX3jFHEMIuu/uzrTeMb", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [#"JobNo." = _t, TA = _t, #"Progress hrs" = _t, #"Progress Date" = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Progress Date", type date}, {"Progress hrs", Int64.Type}}),
    #"Added Custom" = Table.AddColumn(#"Changed Type", "Custom", each if Text.Contains([TA], "TA") then [TA] else null),
    #"Added Index" = Table.AddIndexColumn(#"Added Custom", "Index", 1, 1, Int64.Type),
    #"Grouped Rows" = Table.Group(#"Added Index", {"JobNo."}, {{"Count", each _, type table [#"JobNo."=nullable text, TA=nullable text, Progress hrs=nullable number, Progress Date=nullable date, Custom=text]}}),
    #"Added Custom1" = Table.AddColumn(#"Grouped Rows", "Custom", each Table.FillDown([Count],{"Custom"})),
    #"Expanded Custom" = Table.ExpandTableColumn(#"Added Custom1", "Custom", {"TA", "Progress hrs", "Progress Date", "Custom", "Index"}, {"TA", "Progress hrs", "Progress Date", "Custom.1", "Index"}),
    #"Sorted Rows" = Table.Sort(#"Expanded Custom",{{"Index", Order.Ascending}}),
    #"Removed Columns" = Table.RemoveColumns(#"Sorted Rows",{"Count", "Index"}),
    #"Renamed Columns" = Table.RenameColumns(#"Removed Columns",{{"Custom.1", "Updated TA"}})
in
    #"Renamed Columns"

Result is as below.

Best Regards,
Rico Zhou

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