field2 rules
Every EN 16931, Peppol and XRechnung rule that constrains BT-135. If one of them fails, the others are usually worth a look — a wrong value in one field tends to break several checks at once.
| BR-30 | fatal | If both Invoice line period start date (BT-134) and Invoice line period end date (BT-135) are given then the Invoice line period end date (BT-135) shall be later or equal… |
| BR-CO-20 | fatal | If Invoice line period (BG-26) is used, the Invoice line period start date (BT-134) or the Invoice line period end date (BT-135) shall be filled, or both. |
Nothing is stored, and the whole invoice is checked, not just this rule. A PDF only works if it is Factur-X / ZUGFeRD — a PDF with the invoice XML inside it.