I wonder if the Queen can order a beheading for any show-runner who saw fit to radically change the exterior of the TARDIS.
For those who might not know, TARDISes are (were?) equipped with a chameleon circuit, which ensured that they blended in perfectly to whatever environment that they happened to find themselves in. For example, The Master's TARDIS once landed in Castrovalva (one of the best episodes ever), and appeared as a
doric column. At other times, it appeared as various statues, a grandfather clock, and once even as a spaceship! (Imagine that!

)
The Doctor's (stolen) TARDIS landed in the mid-to-late 20th Century Shoreditch, and proceeded to blend in, changing its exterior into a then-current-period police box. Thereafter, the chameleon circuit was damaged and has never been replaced, so The Doctor's TARDIS therefore now journeys through space and time locked into this incongruous appearance.
It's one of the great touch-points of the show, that appeals to long-time viewers' sense of nostalgia and continuity. I doubt that there will ever be a sufficient justification discovered for remedying the chameleon circuit.