You can also try to create grouping column
Col Cumulative Sum(1, :Test ID, :Sample Type)
jthi_0-1669361444208.png
Use that with Split
jthi_1-1669361476446.png
jthi_2-1669361485726.png
And then select one row from control colum and fill with previous value
jthi_3-1669361523548.png
and cleanup (remove order column, re-order columns, rename if needed)
jthi_4-1669361565167.png
This works in this fairly simple case, but it is also fairly easy to loose data when using JMP's split platform so be careful with (order column tries to prevent this).
-Jarmo