Castaway Diary: Portal to the Unknown Isles has been delayed to 2027, developer REMIMORY announced on November 2, 2026. The anime-style survival sandbox adventure was previously scheduled to enter Early Access on PC via Steam in the second half of 2026. Alongside the postponement, the studio revealed a four-stage development roadmap, new housing customization themes, and expanded language support.
REMIMORY confirmed the schedule change in an official Steam Community announcement titled “Release Schedule Change, Roadmap, and New Themes Reveal.” The developer explained that the delay is primarily intended to improve the game’s overall quality and polish. The studio also cited unexpectedly strong interest from players following the game’s initial reveal as a factor in its decision to extend development.
The revised roadmap begins with a Steam playtest scheduled for the first quarter of 2027, covering January through March. REMIMORY plans to open registration when the playtest build is ready and the official testing announcement is published. No specific testing date or registration window has been confirmed.
Following the playtest, the developer intends to release a public demo, participate in Steam Next Fest, and eventually launch the game in Early Access. These four milestones establish the planned sequence of development activities, although REMIMORY has not provided individual dates for the demo, festival participation, or Early Access release.
The roadmap also places Castaway Diary among several PC titles adjusting their Early Access schedules. Other recent changes include Emberville's move to January 7, 2027, while Steam Next Fest remains an important opportunity for players to try upcoming releases. Valve’s October 2026 Steam Next Fest rankings highlighted the range of demos competing for attention during the event.
Beyond the schedule adjustment, REMIMORY introduced two additional housing customization themes: School and Maid Cafe. Both themes will feature corresponding costumes, expanding the customization options beyond the basic housing designs shown in the game’s initial trailer. The developer released new promotional material showcasing the themes and plans to share further details in future updates.
Castaway Diary: Portal to the Unknown Isles follows a group of girls stranded on mysterious islands. Unlike more demanding survival games, it emphasizes a colorful, relaxed sandbox experience built around exploration, gathering resources, fishing, cooking, farming, and constructing customizable living spaces.
Players will also be able to explore islands and dungeons using mounts, battle monsters, and create outfits for their characters. The game supports online cooperative multiplayer for up to four players, allowing groups to develop their island settlements and explore dungeons together.
REMIMORY additionally confirmed that Russian and Traditional Chinese have joined the game’s supported languages. These additions expand the previously announced selection of English, Japanese, Korean, and Simplified Chinese. The studio indicated that further languages could be introduced, although no additional localizations have been confirmed.
Castaway Diary: Portal to the Unknown Isles remains scheduled for Steam Early Access sometime in 2027. For interested PC players, the first confirmed opportunity to participate in testing is the planned Q1 2027 playtest, with registration details to be announced through the game’s Steam community.
