User blog comment:Arbington/What Garrus in ME3 Means.../@comment-2174252-20110411182431/@comment-2174252-20110411234319

From the article:

“The story begins with Commander Shepard on Earth facing scrutiny related to the events of the recently released Mass Effect 2 DLC, Arrival”

That doesn’t leave too much room for interpretation. Besides LoTSB and Arrival are the two DLC’s we were told were the bridging between ME2 and ME3. They were setting the stage and context for ME3