Will I be charged an overstay fee if my flight is after my visa extension ends?

A user is concerned about their flight scheduled for 1:30 AM on the 11th, which falls after their visa extension expires on the 10th. The discussion suggests that if they manage to check in and pass through immigration before midnight on the 10th, they may avoid any overstay penalties. However, if they exit after this time, they could face a penalty, although for a short overstay (like one day), the fine might be waived, but it could result in a remark in their passport that could complicate future visa applications.