Siehe auch ...
Can't change year tag to YYYY-MM-DD
DD.20150107.2005.CET
Aktion "Tag-Felder importieren"
Quellformat : $left(%YEAR%,4)'=='$right(%YEAR%,2)$mid(%YEAR%,6,2)
... oder ...
Quellformat : $regexp(%YEAR%,'^(\d\d\d\d)-(\d\d)-(\d\d)$','$1==$3$2')
Formatstring: %YEAR%==%DATE%