In osTicket v1.18.2 and v1.18.3, there is an issue with setting holiday dates under Schedule → Holiday Hours. When a user creates a holiday and selects a specific date, the system saves it successfully, but the displayed date becomes one day earlier than what was originally selected. For example, if a user selects 02 June 2026, it is saved and shown as 01 June 2026 after saving.
Another related problem is that once the holiday is saved, it becomes impossible to correct the date. Even if the user tries to edit the entry, the system continues to retain the incorrect shifted date. This makes the issue persistent rather than temporary.
Below are the screenshots and video recording of the system behavior.
