Tropical Cyclone Sigmet cannot be produced for Cancellation and TranslationFailed.

[Mattonius5]

Bug description

IWXXM 2023-1 and 2025: Using following TAC as an example for conversion:

WCPA07 PHFO 180843
KZAK SIGMET T16 VALID 180821/181321 PHFO-
KZAK OAKLAND OCEANIC FIR CNL SIGMET T15 180734/181321=

When you convert it, We generated following IWXXM.
LYPA07_PHFO_180843.txt

This file fails Schematron validation:
"TropicalCycloneSIGMET.TropicalCycloneSIGMET-3: There shall only be one iwxxm:analysisCollection in iwxxm:TropicalCycloneSIGMET"

Since this is cancellation report, analysisCollection should not exist. If you decided to pass this rule by adding single analysisCollection, you get quite expectedly a different Schematron rule violation:
"SIGMET.SIGMET-3: A 'CANCELLATION' report should have appropriately filled elements including iwxxm:issueTime, iwxxm:issuingAirTrafficServicesUnit, iwxxm:originatingMeteorologicalWatchOffice, iwxxm:issuingAirTrafficServicesRegion, iwxxm:sequenceNumber, iwxxm:validPeriod, iwxxm:cancelledReportSequenceNumber, iwxxm:cancelledReportValidPeriod.
Elements iwxxm:phenomenon and iwxxm:analysisCollection shall be absent"
LYPA07_PHFO_180843 - Edited.txt.

Questions, proposals:

1. Why was the rule "TropicalCycloneSIGMET-3" added? To enforce multiple CBs being reported under "iwxxm:supplementaryAnalysisCollection"?
2. I recommend enhancing the "TropicalCycloneSIGMET-3" not to trigger for Cancellation and translationFailed reports.
3. How this should be resolved? By manually editing Schematron rule? If I do that, other recipients will not be able to process the IWXXM file.

Kind Regards,
Matous

Edit one month after ticket created:
The same issue is happening when TranslationFailedTAC is ocupied. Schema in such instance requires presence of only these elements "issueTime", "validPeriod", "issuingAirTrafficServicesUnit" and schematron throws validation error because again "There shall only be one iwxxm:analysisCollection in iwxxm:TropicalCycloneSIGMET".