You haven't misunderstood at all, it was actually an error on our system. The tour with the Cancun add-on should have been 19 days (16+3 days add-on) and this has now been updated on the website.

Thank you for spotting this mistake and apologies for the confusion.

Kindest regards,

Monty

There has been some changes to the itinerary but the 2017 dates will be added to the website in due course.

Kind Regards,

Mildred.