When Oliver and Felicity are talking on the balcony Felicity is wearing a light colored dress under her sweater. They get a call from the bunker, and in the next scene at the bunker Felicity is wearing a black dress.
When the team first learn of Church's plan, Diggle says he knows someone that could help. When they meet after the assassination attempt, Chance introduces himself to Oliver. However the flashback shows that Chance met Oliver 5 years ago in Russia.