Privacy fields are fields like
is_opt out (No Bulk emails)
We have agreed to prioritise a 'yes' value for these fields since that represents a conscious opt out decision. In practice we probably only use do_not_email & is_bulk_out but I am including the others for completeness.
I decided to exclude do_not_trade since we discussed this field in another ticket and set all values for that field to 0 as we do not use it