Daylight Savings Time
Observer is not coded with a specific date in mind. Daylight Savings Time is controlled by the operating system. When the clock rolls backwards or forwards Observer rolls with it, with one exception: packet capture/decode.
Packet capture provides nanosecond time resolution, which none of the rest of the product does. Because of this, packet capture does not rely on the system clock to provide time stamps. It relies on the processor time ticks. When Observer opens it requests the system time and the number of processor time ticks and uses those. This allows Observer to know what date and time it is when a packet is seen.
Because the Observer only asks the operating system for the system time when Observer is started, packet capture does not know that the time has jumped forward or backward. To get this to happen you need restart Observer after the time change. It is that simple.