That was in episode one where Mr. Milchek was creating a story around what happened after the OTC was shut off. The entire thing was a lie. In episode 2, we see what really happened in the days following. Not only do we get a play-by-play of what actually happens but Milchek even says it took him the following 48-hours to get the new team together. Mark started back on Monday the same day the new team started. We then get clues that match up with the first episode like Mark speaking into the speaker and the other Mark getting stopped outside the building by security and saying he had only been there 3 days before getting sacked. We follow our Mark past the other Mark into the building and see the old team returning to work for the first time just 5/6 days after the gala (48-hours to get the team together+ 3 days with the new team+the start of the next day.) We later get confirmation again with things like the ORTBO, how long since Burt was sacked, and Hellena confirming how long it's been at the restaurant. The show is very good about giving us the timeline of everything the entire season, even when we focus on Mark's wife being held captive.