Convert quarterly date (Q3 2022) to numeric date

Make that field text. Working with ANY or ABC/123 is a pain.
I get this:

The formula I used in the custom column is:

try 
   Date.FromText([Target Dev Start]) otherwise 
   Date.StartOfQuarter(
      #date(
          Number.From(Text.End([Target Dev Start],4)), 
          Number.From(Text.Middle([Target Dev Start], 1, 1)),
          1
       )
    )

The full M code is

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WCjRUMDIwMlaK1YlWMtQ31IdwYgE=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [#"Target Dev Start" = _t]),
    #"Added Date" = 
        Table.AddColumn(
            Source, 
            "Date", 
            each try Date.FromText([Target Dev Start]) otherwise 
                Date.StartOfQuarter(
                    #date(Number.From(Text.End([Target Dev Start],4)), Number.From(Text.Middle([Target Dev Start], 1,1)), 1)
                ),
            type date
        )
in
    #"Added Date"

 How to use M code provided in a blank query:
1) In Power Query, select New Source, then Blank Query
2) On the Home ribbon, select "Advanced Editor" button
3) Remove everything you see, then paste the M code I've given you in that box.
4) Press Done
5) See this article if you need help using this M code in your model.