https://professional.wiki/en/extension/wikibase-edtf
Add support for the Extended Date/Time Format (EDTF) Specification to Wikibase. Learn more about the free and open-source Wikibase EDTF extension.
wikibaseedtfprofessional
https://packagist.org/packages/professional-wiki/edtf
PHP library to parse, represent and work with dates that follow the Extended Date/Time Format specification.
professionalwikiedtfpackagistorg