Bearing a European matrilineal type could not be dated based on the current observation. You never know what time the introduction of that lineage occurred. In fact, in Han Chinese across China, about 1% of individuals (depending on different regions, some regions even higher) contained European mtDNA type. See two papers at http://mbe.oxfordjournals.org/cgi/content/full/21/12/2265
and
http://www.journals.uchicago.edu/AJHG/journal/issues/v70n3/013347/013347.html