Duplicate row for each item in column - powerquery

Question

I can do things in PowerQuery but I can't find how to achieve the following result:
Before:
After:
The goal is to duplicate the last row (filtered with Project Code=null) for each item in Project Code column. I think duplicating the row as is is important to keep the Metadata Table and expand it later.
Thank you very much for your help.

Answer 1

Try this
Grab all rows except null row
Get unique values of Project column in a list
Grab null row
Create row with the list and expand it
Put the two tables back together.
let Source = Excel.CurrentWorkbook(){[Name="Table1"]}[Content],
AllButNull=Table.SelectRows( Source, each ([Project Code] <> null)),
UniqueProjects=List.Distinct(AllButNull[Project Code]),
OnlyNull = Table.SelectRows(#"Added Custom", each ([Project Code] = null)),
#"Replaced Value" = Table.ReplaceValue(OnlyNull,null, UniqueProjects,Replacer.ReplaceValue,{"Project Code"}),
#"Expanded Project Code" = Table.ExpandListColumn(#"Replaced Value" , "Project Code"),
combined = AllButNull & #"Expanded Project Code"
in combined
Alternately, grab the last row instead of the null row:
Grab all rows except last
Get unique values of Project column in a list
Grab last row
Create row with the list and expand it
Put the two tables back together.
let Source = Excel.CurrentWorkbook(){[Name="Table1"]}[Content],
AllButLast=Table.RemoveLastN(Source ,1),
UniqueProjects=List.Distinct(AllButLast[Project Code]),
OnlyBottomRow = Table.LastN(#"Added Custom", 1),
#"Replaced Value" = Table.ReplaceValue(OnlyBottomRow,null, UniqueProjects,Replacer.ReplaceValue,{"Project Code"}),
#"Expanded Project Code" = Table.ExpandListColumn(#"Replaced Value", "Project Code"),
combined = AllButLast & #"Expanded Project Code"
in combined