Currently NIE DUoS bill readings on a priority basis with Meter Works/Meter Reader Hand-Held Unit (HHU) taking precedence over all other read
types.
This Discussion Request proposes that when the billing window for a particular MPRN is opened (in line with the meter reading schedule), the first
actual reading received will be DUoS billed regardless of type. The rationale for this change is further harmonisation.
In addition, NIE have a requirement to store all readings regardless of type to maintain an accurate read history for each MPRN

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