Plot hole: In the middle of chasing the Doctor, Stor abandons the idea of controlling Gallifrey in favour of destroying it for no readily apparent reason.
Plot hole: Leela's decision to stay with Andred is very sudden. They barely speak during the serial.
Answer: TARDISes are generally available for properly authorised use on Gallifrey; they're not usually assigned to a particular Timelord on a long-term basis. The Doctor stole his when he left his homeworld.
Tailkinker ★