Sometimes we get a data dump from TIDAL that says This album will be available for streaming on this day – our system is built to handle this, and the album will show up at the right time when we have this type of advance notice.
Other times, especially with regards to “surprise” releases, or “event” releases (Rihanna, The Beatles, Adele’s single"), TIDAL flips the switch and our database needs to catch up, which can take a day or two. We’re working on some plans for making this better, but that’s the current state of affairs.
Regardless of the normal process, I just looked and it appears that we may have missed an update, putting us slightly more behind than normal --@jeremiah and I are looking into it. Thanks for the report.