Compute duration when start time and end time are in the same column

Hi sciomac 

How does this look?
Let me know if you have any questions.

If this solves your issues, please mark it as the solution, so that others can find it easily. Kudos 👍are nice too.
Nathaniel

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("fdS9boMwEADgV4mYI+XO9vnAczp06tBKHVBURQpDVTWtEEvfvkeIobh3LDEEfblf0rbV47HaV69f/UfXv92uj+ehk+Pl/fN2/HyPx1N/6fqdPD/t24pjA/IdonwAHtAdHCDLDSffJEdy9Tyc+2E3TL+BUZ7eIapQVEw+yNXD9aIoJ/exRAgJQyJQwsUMvQUp+ViGm1WwVBS4VR2pMIzVkTOri5bi5Nz/cA4yZLWZY21+Kq+QMFdYb8jQFJkurNlgpAW818igL8woQ4JyEgtDtTWieJrEX5X7wuDmYGG9ZJAC2/Nj8BbEdKtAmx9DMBTx1MuyKZQh2ZCUPZNAdxhVKBs6LhqW3ZwZm0w2rXz7ljTrPISwHkKARLW9nwyNBVFGYU0PIStaNUX+WihsREPUnWSJ5bu3IGcip5WG2S2bsoZk9KTOMFhQVozLNGdFWproE+KU50pJkqdf", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type text) meta [Serialized.Text = true]) in type table [Column1 = _t, Column2 = _t, Column3 = _t, Column4 = _t, Column5 = _t, Column6 = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Column1", type text}, {"Column2", type text}, {"Column3", type text}, {"Column4", type text}, {"Column5", type text}, {"Column6", type text}}),
    #"Promoted Headers" = Table.PromoteHeaders(#"Changed Type", [PromoteAllScalars=true]),
    #"Changed Type1" = Table.TransformColumnTypes(#"Promoted Headers",{{"ID", Int64.Type}, {"Worker_ID", Int64.Type}, {"Date", type date}, {"Time", type time}, {"Type", type text}, {"Order ID", Int64.Type}}),
    #"Changed Type2" = Table.TransformColumnTypes(#"Changed Type1",{{"Worker_ID", type text}}),
    #"Filtered Rows" = Table.SelectRows(#"Changed Type2", each ([Type] = "Start time")),
    #"Renamed Columns" = Table.RenameColumns(#"Filtered Rows",{{"Time", "Start time"}}),
    #"Removed Columns" = Table.RemoveColumns(#"Renamed Columns",{"Type"}),
    #"Appended Query" = Table.Combine({#"Removed Columns", Endtime}),
    #"Sorted Rows" = Table.Sort(#"Appended Query",{{"ID", Order.Ascending}}),
    #"Reordered Columns" = Table.ReorderColumns(#"Sorted Rows",{"ID", "Worker_ID", "Date", "Start time", "Endtime", "Order ID"}),
    #"Filled Up" = Table.FillUp(#"Reordered Columns",{"Endtime"}),
    #"Sorted Rows1" = Table.Sort(#"Filled Up",{{"Order ID", Order.Ascending}}),
    #"Filtered Rows1" = Table.SelectRows(#"Sorted Rows1", each ([Start time] <> null)),
    #"Sorted Rows2" = Table.Sort(#"Filtered Rows1",{{"ID", Order.Ascending}}),
    #"Removed Columns1" = Table.RemoveColumns(#"Sorted Rows2",{"ID"})
in
    #"Removed Columns1"

Will post pbix soon.