Man, I wish I had a crystal ball for this one! Sylvia Day's releases always feel like they take forever, but honestly, that's because she pours so much into her stories. Last I checked, there hasn't been an official announcement for her next book, but if we go by her past patterns—like the gap between 'Bared to You' and 'Reflected in You'—it could be another year or two. She’s pretty active on social media though, so I’m constantly refreshing her pages for hints. If you’re jonesing for something similar, have you tried 'The Crossfire Series' fanfics? Some are surprisingly good while we wait.
Also, her 'Shadow Stalker' series is worth revisiting if you’re into paranormal romance. The world-building there is wild, and it’s a nice detour from her contemporary stuff. Fingers crossed she drops a teaser soon—her newsletter might be the first place to catch it!