>>15824233I haven't read it(other than a brief skim in the shop) but the behind the scenes book with all of RTD's emails, scripts, writing team meeting minutes and writing notes from seasons 1-4 of Doctor Who, I think mentions introducing a Time Agent to the series and discusses with Moffat how to do it and some character notes.
I don't know if anyone remembers but Jack was meant to have had two years wiped from his memory and he was kind of pissed about it at the time. I assume that's forgotten now that he's well over a few thousand years old in Torchwood.
Also I just noticed he, River and Liz 10 are in the 51st century. Moffat quite likes that time period.