not sure if this is a bug or not, but the mastery levels in the grammar quizzes seems odd - for example, I have the three grammar points in the N1 'clauses' lesson up to 95-100% mastery, but the lesson itself shows as 63% mastered.
Another issue with this - the following 3 sections (first screenshot) have all grammar at 100% but don't list it, and I have several other sections (example in second screenshot) that are listed at over 100% (apologies for the color, I forgot my blue light blocker was on)
Currently all the updated JLPT lessons show 0% mastery. I'm pretty sure I've studied at least a few of the first five lessons on the N5 list, though I'm not sure which ones. At least those ones should show something other than 0%.