I used this formula and it works for Lot 1; but I don't know how to expand it for PM01 to PM12 and for Lot 2 and 3.
If(
:Panel Member == "PM01" & :Well # == "A01" | :Panel Member == "PM01" & :Well # == "B01" | :Panel Member == "PM01" & :Well # == "C01" |
:Panel Member == "PM01" & :Well # == "D01" | :Panel Member == "PM01" & :Well # == "E01" | :Panel Member == "PM01" & :Well # == "F01",
"Lot 1",
"TBD"
)