Doctor Who: 9 Reveals From The Revolution Of The Daleks Trailer
2. Captain Jack’s Commentary
Jack is finally back, but he’s not all cheese and charm at the moment. He speaks to presumably Ryan, Graham, or Yaz (or all three) about being separated from the Doctor;
“How many people in the universe get to meet the Doctor, let alone travel with her? Being with the Doctor you don’t get to choose when it stops, whether you leave her or, she leaves you”.
This could presumably be down to the fact that the “fam” have no idea where the Doctor is, yet alone whether she’s still alive following the events of ‘The Timeless Children’. Maybe they’re questioning their worth as her friends, and Jack would know all about being left behind.