There are also signs that the new Doctor could be announced as early as next month.
Serious consideration is being given to unveiling the new Doctor on a surprise Doctor Who Confidential as happened with Matt Smith’s unveiling in 2010, with some sources confirming that it will be in August.
However timings are always a very relative thing when selecting Time Lords.
Doctor Who’s 50th anniversary show will feature one of the five former doctors who wielded the Sonic Screwdriver before the Eccleston reboot, RadioTimes.com understands.
According to sources, one of either Colin Baker, Paul McGann, Tom Baker, Sylvester McCoy or Peter Davison will be in the feature length special episode alongside Tennant’s Doctor and the current incumbent Matt Smith.
Tennant’s appearance as the tenth Doctor has been confirmed in the story which will also feature the Daleks and the classic 1975 shapeshifting villains the Zygons.