cbc:IssueDate | cbc:DueDate | cbc:TaxPointDate | cbc:StartDate | cbc:EndDate | cbc:ActualDeliveryDate

string-length(text()) = 10 and (string(.) castable as xs:date)

udt:DateTimeString

normalize-space(@format) = '102' and string-length(text()) = 8 and matches(normalize-space(text()), '20[0-9]{6}')