In Sheet1 (the codename)
In B19 down is a list of unique items:
xx
yy
zz

In Sheet2 (the codename)
In A3 down is another list of unique items:
aa
yy
bb

I need a sub to compare the 1st list with the 2nd, and to append any items
in the 1st which are not found in the 2nd list, to the bottom of the 2nd
list. Example, for the sample data above, the 2nd list should finally look
like this:
aa
yy
bb
xx
zz

(xx, zz are appended)

The sub is to reference the 2 codenames
Thanks for insights