Is this Overstay?

[TheKaledonian]

My wife is Chinese.  I am British. We live in Australia.  She has visa, issued in China by France, which is from 1 July 2016 to 30 June 2017, and which permits 90 days per visit.  We plan to enter Shengen states on 15 June 2017 and stay until 15 July 2017. We will cross by Ferry with motorhome Dover to Calais to Dover. She will have entered before expiry of the visa and will have exited before the 90 days. Would this count as an "Overstay"? Is there a way to "extend" the visa while in Schengen state, or before travel? Or will she need a new visa? (Just for comparison, my visa for China allows 60 days in China so long as I enter before the expiry date of the visa)

[yaris]

Hi, I understand your wife's visa expires on 30 June 2017. That is the day on which she must leave the Schengen zone at latest. After the expiration of visa, she is not allowed to legally stay within the Schengen zone. An extension to Schengen visa is possible, however, one needs to have a real reason for that, see here for more details:

Extension to Schengen visa
(http://www.maxi-pedia.com/forum/index.php?topic=1054.msg2770#msg2770)