dim_Range? One set of time ranges that classify multiple different columns

Hello, Cheywork91 try this on your data. If you need to modify all columns in the table then duration/other columns selection steps are not necessary - just Table.ToColumns the whole table. Otherwise modify duration_column_names manually. 

let
    dt = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WKjFU0lEy0IOSxkqxOkAxIzAPQhpYQMRMwTwIaWQEETMH86CkKUTM0hLMhVIWQN2xAA==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [c1 = _t, c2 = _t, c3 = _t]),
    data_table = Table.TransformColumnTypes(dt,{{"c3", type number}, {"c2", type number}}),
    lt = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("LcpBDgAQDETRu3SNzNCSuIq4/zUU3fzFy19LUKpJEmCC2UuTnS6Hsl9tCB3B7c36Z35TXznh6z4=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [d = _t, range = _t]),
    lookup_table = Table.Sort( Table.TransformColumnTypes(lt,{{"d", type number}}), "d" ),
    lookup_d = List.Buffer( lookup_table[d] ),
    lookup_range = List.Buffer( lookup_table[range] ),
    f = (x as list) => 
        List.Transform(
            x,
            (w) =>
                let 
                    a = List.PositionOf( lookup_d, w, Occurrence.First, (a, b) => a >= b )
                in try lookup_range{a} otherwise null
        ),
    duration_column_names = {"c2", "c3"},
    other_column_names = List.Difference( Table.ColumnNames( data_table ), duration_column_names ),
    duration_columns = 
        List.Transform(
            Table.ToColumns(
                Table.SelectColumns( data_table, duration_column_names )
            ),
            each f (_)
        ),
    other_columns = Table.ToColumns( Table.SelectColumns(data_table, other_column_names) ),
    final_table = Table.FromColumns(other_columns & duration_columns, other_column_names & duration_column_names)
in
    final_table