During a VR briefing Hideki reveals that it has been one year since Takeshi's sister, Reileen Kawahara, was (supposedly) killed alongside Quellcrist Falconer in the attack on Stronghold. This means that Altered Carbon: Resleeved is set in 2131, during Takeshi's time working as a mercenary. The anime takes place three years before CTAC finally caught up to Takeshi and put his stack on ice. That's 253 years before the main events of Altered Carbon season 1, and 283 years before the events of Altered Carbon season 2. However, its story has strong ties to both seasons - as an early twist reveals. screenrant.com