I'm not familiar with the terminology. What are RD routes? What is the 911 system? Soz if the questions are dumb. We got a rural route that has sectioned streets like M n M 1/2 but you gotta know when the line starts by the power boxes. We also have a 300+ mile gurlac route that has like 40 stops but you gotta know where ya going. I haven't done that one yet.
Rural Delivery areas, no house numbers, just RD 356, 357, 358, etc. The system the USPS used.
The big problem for UPS with RD routes was you might have 10 houses on a long flag lot road. Some were build before others so their RD number would be lower than the newer house. You needed to know what house to go to? They often were not marked. Also, if a newer house was built near the older, their RD number might be higher even though they are first in order! They kept counting up. Sometimes the would add letters like RD 1-396A, RD 1 396B!
Another headache was often in a middle of a long road, the RD loop would stop. The USPS would back up and start down the same street on the other side. That point would begin another RD loop with another name. If you didn't know the RD breaks, you were screwed!
The 911 system forced each homeowner to use a specific address. It went in sequential order up and down every street and lane.