In the changed world, Kevin repeatedly mentions going over to his friend Dre's house. Salli Richardson-Whitfield was pregnant during Season 3 and had a son named Dre before Season 4.
When Carter and Dr. Grant try to connect the electrical cables they find that they are too short and must stretch them just as Dr. Emmett Brown had to in the movie Back To The Future. Also, Henry tells Jack that he is almost "outta time". Dr. Brown's time-traveling Deloran's license plate reads: "Outatime".
Dr. Grant mentions how he thought there would be Robotic Servants in the future. This reflects James Callis' previous series, Battlestar Galactica (2004), in which the Cylons were built as robotic servants.