Originally Posted by Black Guardian:
“with no guarantee that they will return to the correct point in time. they might get back to find Saxon has been in power for some time.”
It was signposted near the start of the episode and we know that RTD is rarely subtle. It'll be Jacks time device and it's a fair bet we will get the following scene:
The Doctor: "Your time device"
Jack: "But it's not accurate, we could end up anywhere in time"
The Doctor: "Ah but I'm a genius remember, just a quick rewiring and we'll be good to go"
Cue Sonic Screwdriver moment.
Cue The Doctor grinning inanely at Jack then the camera.
Thats my theory BG