How to change existing code that highlights duplicates?

I have attached a copy of an excel sheet that's main function is too highlight duplicated postcodes for work.

I wish to change the layout slightly by inserting two extra columns after column H, moving everything along.
The two new columns will be for more sectors so 5 fit along one row.
The drop of the spreadsheet, whilst currently 59 rows down needs to change to 70 rows down.

What I can't figure out is how to change the code so that the extra two columns are also included in the highlighting & also included in the extra 11 rows to be added at the bottom?

Too activate the highlighting click on Cell A1 & to deactivate B1

Appreciate any help. Many thanks.