Answer

In Jain tradition, Pakhi (Pakkhi Pratikraman) is observed on the 14th day of each lunar fortnight, so the exact Gregorian dates for December 2026 depend on the Jain lunar calendar used in your region or sampradaya.

Sorry, I can only provide information that is clearly established within Jain tradition. For an exact December 2026 date, please check a trusted Jain Panchang for your location.