There is no denying that "Sex Education" has become one of Netflix's most popular shows, following the romantic lives and friendships of Moordale students. Hence, it comes as no surprise that fans are thrilled about its upcoming new season.

"Sex Education" Season 4 is said to premiere on Netflix next year, but not all of the cast are returning to reprise their roles. Here is everything fans need to know about the stars who have quit the series ahead of the fourth instalment and what they're up to instead.

Tanya Reynolds

The 30-year-old English actress told she was sad to be not returning for "Sex Education" Season 4. She said, "I miss the gang a lot. But onwards."

Tanya Reynolds joined the popular Netflix series, portraying a Moordale High student who tries to lose her virginity in the first season and then starts dating Ola in the second instalment.

This year, Tanya portrayed Queen Victoria in "The Baby" series, which centres on a woman who is unexpectedly landed with a baby. She is also set to appear in the imminent film "Harold and the Purple Crayon" together with Zooey Deschanel.

Patricia Allison

The 27-year-old English actress shockingly announced her departure from the series in July to focus on other projects. During an appearance on "Capital 1Xtra," she said, "I absolutely have loved being on Sex Education so so much, and playing Ola, but unfortunately, I won't be joining the team for season four."

When asked the reason why she had to quit the show, Patricia Allison shared, "Some other opportunities have come up. So, I've been doing it for three years, and I've like genuinely loved it."

For starters, Patricia Allison played Ola in "Sex Education," who first dated Otis Milburn (Asa Butterfield) before moving on with Lily Iglehart (Tanya Reynolds).

Patricia is set to appear in the upcoming action movie called "Paradise," which also stars "Friends" actor Tate Donovan. The said film centres on Ella Patchet (Patricia) as she tries to uncover the secrets, corruption and lies surrounding her beloved father's murder.

Rakhee Thakrar

The third star who will not be reprising her role in "Sex Education" Season 4 is Rakhee Thakrar, who played teacher Emily Sands. The 38-year-old English star cryptically shared that she "can't really talk about why" she won't be in the next instalment.

The actress told Daily Star, "I'm not part of the new series. There is nothing bad about Sex Education." Miss Sands was known for her closeness with Maeve (Emma Mackey) and her relationship with fellow teacher Colin Hendricks (Jim Howick).

Rakhee Thakrar is set to appear in the ITV cold case murder drama called "Karen Pirie" and in Hallmark show titled "My Happy Ending" with Andie MacDowell and Miriam Margolyes.

Simone Ashley

The 27-year-old British actress quit "Sex Education" ahead of the premiere of its fourth season to focus on her role in "Bridgerton." As a matter of fact, the actress said on "This Morning," "I'm a Bridgerton gal now!"

In the series, Simone Ashley played Olivia, who was a member of the mean girls group called "The Untouchables," which included Anwar (Chaneil Kular) and Ruby (Mimi Keene). She is presently filming "Bridgerton" Season 3 after joining the cast in the previous instalment as the ladylove of Anthony Bridgerton (Anthony Bailey).

Netflix has yet to announce the official premiere date of "Sex Education" Season 3, but it is predicted to premiere in early 2023.

Sex Education
Sex Education Jon Hall/Netflix