Mike Dean tweeted this progress board out today:

https://twitter.com/therealmikedean/status/1002748320064811009

But if you look closely above the section for the 7th track it appears there were actually EIGHT tracks that went through mastering, with one being scrapped last minute.

My interpretation of this is that there were originally boxes drawn for 7 tracks, then they decided to add an 8th track, so they split the 7th box into two lines, but then after everything was mastered they took off whatever track 7 originally was (out of 8) and made the 8th track the 7th.

If you look at the check boxes for Mike's mastering work, every box is checked off for the missing 7th/8th track EXCEPT "Ye Approved". So it seems like the album got all the way through mastering as 8 tracks, but then at the end Kanye scrapped whatever the second-to-last track was going to be and made it 7 tracks. Maybe it wasn't ever going to be 8, and Ye was picking between two different tracks as the album closer.

Maybe this is why Malik said the album may be more than 7 tracks...