Replace value in field automatically (auto-correct?)

Question

I'd like to replace occurrences found in Column A (cells A2:A200) so that if I enter 2/02/002 or 343 or 98/098 it auto-replaces it with UKD002/UKD343/UKD098.

Is this possible?

Answer 1

=ARRAYFORMULA(IFERROR(VLOOKUP($C$2:$C, QUERY({
 IF(LEN(A2:A)=1, "UKD00"&A2:A,
 IF(LEN(A2:A)=2, "UKD0"&A2:A,
 IF(LEN(A2:A)=3, "UKD"&A2:A, A2:A)))}, 
 "select Col1,count(Col1) 
  where Col1 is not null 
  group by Col1 
  label count(Col1)''"), 2, 0)))

demo spreadsheet