Timestamp format

Hi, Anonymous 
I did test it on my own and I can't replicate your issue:

Make sure, you put "en" as culture argument when you're choosing the date/time/timezone data type. And then you create new column like this:

Here's my Query, you can copy it to your Blank Query in Power Query and see for yourself:

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMtE3MtU3MjAyUjCyMjC1MjJQCPBV0DYwsDIwUIqNBQA=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Date = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Date", type datetimezone}},"en"),
    #"Inserted Time" = Table.AddColumn(#"Changed Type", "Time", each DateTime.Time([Date]), type time)
in
    #"Inserted Time"