The article you're referring to is likely about the Christmas specials of the revamped Doctor Who series that aired from 2005 to 2013. Here's a brief overview:
The tradition began under showrunner Russell T Davies and continued with Steven Moffat, making the Christmas Day episode a "yearly tradition". Doctor Who 2005 2013 Christmas Special The Time...
In the episode's climax, as the Doctor prepares for a final stand against the Daleks, Clara pleads with the Time Lords through the crack in time to save him. The Time Lords respond by bestowing a completely upon the Doctor. This explosive burst of regenerative energy destroys the Dalek fleet and allows the Doctor to rejuvenate before his final transformation into the Twelfth Doctor, played by Peter Capaldi. Themes and Significance The article you're referring to is likely about
"The Time of the Doctor" was a pivotal episode in the history of Doctor Who, marking the end of Matt Smith's era as the Eleventh Doctor. The special also provided closure for long-time fans, as the Doctor's fate was finally revealed. The Time Lords respond by bestowing a completely
Critics noted the episode's use of Christmas motifs as a metaphor for rebirth and hope , despite the somber tone of the Doctor's "death". Reception and Impact Viewership: It was the second most-watched programme on Christmas Day 2013 in the UK, peaking at 10.2 million viewers during the final five minutes. Critical Reaction: Reviews from Radio Times The Spoilist
The Doctor stays for hundreds of years, defending the town until he reaches extreme old age. He reveals to Clara that he is on his final life, having used all 12 of his regenerations (including the War Doctor and a previous aborted regeneration). The New Regeneration Cycle: