http://movieplayer.it/articoli/doctor-who-steven-moffat-a-lucca-comics-2015_15104/
Key bit translated.
"As for River Song ... well, I was very, very tired, it was the end of the series and I didn’t know if I’d be back for another year, so I wondered what I would do if this was my final episode. I love River, I enjoy writing her, and even Russell has told me for some time that I should bring back River with Capaldi. That's why I brought her in the series, because it could have been the end, because I love to write her, because she has to meet the new Doctor and to play Alex Kingston against Capaldi’s eyebrows."
Has he finally completed his transformation into the new JNT; wanting to leave but having to stay because there's no one to replace him?
Key bit translated.
"As for River Song ... well, I was very, very tired, it was the end of the series and I didn’t know if I’d be back for another year, so I wondered what I would do if this was my final episode. I love River, I enjoy writing her, and even Russell has told me for some time that I should bring back River with Capaldi. That's why I brought her in the series, because it could have been the end, because I love to write her, because she has to meet the new Doctor and to play Alex Kingston against Capaldi’s eyebrows."
Has he finally completed his transformation into the new JNT; wanting to leave but having to stay because there's no one to replace him?