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KSEF-BUS-302 BATCH CHECK Error KSeF Guard Only

Invoice date regression in sequential number series

Regresja daty faktury w sekwencji numerów

Problem

Guard detected an issue-date (P_1) regression within a sequential invoice number series — an invoice with a higher number has an earlier date. Batch heuristic — not enforced by KSeF, but may indicate a numbering or dating error.

How to Fix

Check the order of dates and invoice numbers in the batch — an invoice with a higher number should not have an earlier issue date.

Source Reference

KSeF Guard batch heuristic (chronological monotonicity of P_1 within sequential P_2 series)

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Source Quote

“Invoice dates (P_1) must be in non-regressing chronological order within sequential submissions.”
Description SHA-256: 6436d6642515…

Justification

BUSINESS LOGIC

Legal Basis Chain

1

KSeF Guard heuristic — chronological monotonicity in a batch

KSeF Guard heurystyka — monotoniczność chronologiczna w partii

“[KSeF Guard heuristic] BUS-302 has no direct basis in the VAT Act — the Act does not require dates (P_1) to increase chronologically within a sequential invoice number series (P_2). The rule is an operational heuristic that catches typical manual-dating mistakes or system-clock drift: within a batch processed together, an invoice with a higher serial number should bear a date no earlier than an invoice with a lower number.”
KSeF Guard heuristic (chronological monotonicity)