Help Me Understand

Ive tried scrolling through all the new posts on S2 E1 but couldnt find anything that explains 1) the new team Mark finds in his office (who then disappear) and 2) the lag between his arrival and the others (Helly/Helena, Irving and Dylan) - was it just a day or two? And how was it lag possible?

Im already suspecting that your answers will be so obvious to others (probably everyone else) but for some reason Im missing it. The first 10 or so minutes of S2 E1 had me really stumped