The Nominated Delivery Day (NDD) model extends the IVR7 vehicle routing schema with periodic scheduling capabilities. Where the IVR7 model plans a single day of routing, the NDD model plans across a multi-day period (such as a week or a month), assigning jobs to specific days and optimising the routes on each day simultaneously. The schema identifier for the NDD model is ndd-cmibu6krtqja.

The key differences from the standard IVR7 model are:

• Profiles on each job define the visit frequency and allowable day patterns (e.g. once a week, twice a week, or custom cycles).
• Vehicles define a vector of shifts rather than a single shift, providing working hours for each day in the period.
• Task sequences include a dayIndex to specify which day a particular sequence applies to.
• The dimension configuration includes weekLength and periodLength fields that define the planning horizon.
• The solution response returns a Pareto frontier of compact solutions, allowing the user to explore tradeoffs before requesting full route detail.

The NDD model is well suited for scenarios such as regular delivery rounds, periodic service visits, or any routing problem where customers require visits at defined frequencies over a planning period.