I would see if Linksys has newer firmware for the new date and other than that - I would not worry about it. When the old date comes then it will change and be correct.
Meh, if you are happy with the stability of the firmware you have and can live with the inconvenience of the time being slightly off a few weeks during the year, let it be. Wait a few weeks and the time will be correct: "Since 2007, daylight saving time starts on the second Sunday of March and ends on the first Sunday of November, with all time changes taking place at 02:00 local time"