This summer, my friend from Thailand will come to see me in Prague, Czech Repulic. He applied for a Schengen tourist visa type C and received it, valid for 30 days with 15 days of the stay.
Due to the miscalculations, he booked the following flights:
Arrival in Prague 28th July, 13:30 (1:30 pm)
Departure from Prague 12th August, 12:30 (12:30 pm, half past noon).
Overall it makes 16 days. He tried to change the flight back on 11th August, but is having problems.
The travel agency fees are too high to change the flight as well as the cost of the confirmation of the change for the international calls. Moreover, it isn't replying to his messages, so it is unlikely that he'll change the flight.
What are consequences of overstaying in Prague by 12 hours (technically one day) and what is the likely scenario? What can we do except canceling the flight? Is there a way to extend the duration of stay in Prague?