Revealing mistake: In episode four, the camera wobbles when the Doctor brings the gun to Stael.
Other mistake: Several shots are repeated during the implosion of the priory.
Continuity mistake: The TARDIS is missing its light the first time it's seen.
Continuity mistake: In the opening TARDIS scene, after the TARDIS lurches from the time scanner, the Doctor's hat rack can be seen standing upright. Then Leela picks it up in the next scene.
Answer: It was never destroyed on-screen; it was intact at the end of the TV movie, and destroyed by the start of the 2005 series. It was destroyed in the novel "The Ancestor Cell," but in a completely different manner to what happened in the series.
DaveJB