"I'm not [returning], actually, which is sad, very sad," Reynolds told us while promoting her upcoming Channel 4 comedy I Hate You.
"It's just the natural progression of these shows – when you have such big ensemble casts and so many characters, I think you have to let a few older characters go to make way for newer ones, which is absolutely the right thing, the way it should happen."
Reflecting on her time playing alien-obsessed student Lily, Reynolds added: "I loved every minute of it and I loved Lily with my whole entire heart. Three seasons was just a really perfect amount for me."
The news of Reynolds' departure from Sex Education follows a similar reveal from her co-star Patricia Allison, who played Lily's girlfriend Ola in the series.
Earlier this month, Allison announced during an interview on Capital Xtra Breakfast that she similarly would not be back for more episodes.
"I won't be joining the team for season 4," she said. "I absolutely have loved my time on Sex Education, and I'm so sorry to have to break that to you guys.
"I've been doing it for three years and I've loved it."
A fourth season of Sex Education was officially greenlit by Netflix in September 2021 – but with a number of cast members not returning, including Reynolds, Allison and Bridgerton's Simone Ashley, and Moordale Secondary School closing its doors in the season 3 finale, it seems the next season could end up looking very different.
Reynolds' next project, I Hate You, is coming soon to Channel 4 and is from Friday Night Dinner creator Robert Popper.
The six-part series will see Reynolds and Melissa Saint play best friends who end up in a string of outlandish situations, encountering some eccentric characters along the way, as they navigate today’s intense, complicated world.
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I Hate You is coming soon to Channel 4. Sex Education seasons 1-3 are streaming now on Netflix – visit our Comedy hub for more news, interviews and features, or find something else to watch with our TV Guide.
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