Doctor Who Season 13: Ruth Doctor Will Return, Confirms Producer

screenrant.com:

Doctor Who executive producer Matt Strevens has confirmed Jo Martin's mysterious Ruth Doctor will return in the next two specials. Doctor Who season 12 radically transformed the Doctor's status quo, revealing the enigmatic time traveler is not a Time Lord at all. Rather, she is the Timeless Child, a being who may well predate the universe itself. What's more, the season introduced the so-called "Fugitive Doctor," played by Jo Martin, who's since been confirmed to be a pre-William Hartnell incarnation.

Jodie Whittaker's Thirteenth Doctor first encountered Martin's Doctor when she was living on Earth under the identity of Ruth Clayton — which is why a lot of fans have taken to calling her the «Ruth Doctor.» The Doctor gradually learned this mysterious incarnation had worked for a covert organization called the Division, and had ultimately rebelled against them, attempting to hide on Earth by using a Chameleon Arch to pretend to be human. There are still a lot of unanswered questions about the Ruth Doctor, some of which will be explored in an upcoming Doctor Whocomic. But it seems her story hasn't been relegated only to the comics — because she'll be returning on screen later this year.

Related: Doctor Who Finally Fixes The Doctor's Worst Companion Mistake

Speaking at the Gallifrey One fan convention, Doctor Who executive producer Matt Strevens and Jo Martin herself confirmed her story isn't yet over, according to twitter user @_MxtthewHxll_. The next two Doctor Who specials were shot alongside Doctor Who: Flux, so Strevens and Martin are undoubtedly referring to those; the Spring Special appears to be a historical adventure focused on the Sea Devils, creatures from the classic series, so this likely refers to the BBC