MM,
Not really sure what you want here.
Delivery grouping means that all items in the group will be delivered together.
I assume that you mean V_V2 when you are talking about 'Rescheduling'. Please confirm. This is unrelated to MRP; rescheduling means that you want to re-evaluate the availability situation on certain requirements, and reschedule these requirements based upon the current availability situation.
If you have one item in a delivery group that will be delivered 'late', then it means ALL the items will be delivered late, by definition. This is the primary purpose of delivery groups - you are telling the system that the items MUST be delivered together.
Exactly what is your business requirement? Why are delivery groups being created in your business scenario, if not to have them delivered together?
You have the option to manually exclude specific items from a single delivery group; e.g. you could either delete the delivery group for an item, or you could create a second delivery group in the Sales order for the items that are expected to be 'late'.
You also have the option to exclude certain items from rescheduling. One common way is to set the Fixed-date-quantity flag in the Sales order item. In this case, V_V2 will not reschedule the order item, and other items in the same Delivery group will also not be rescheduled.
Best Regards,
DB49