This is probably a really dumb question, but when do things move from expert to master? I see expert says 4 and 6 months, but I’m not sure when it tests again to move something to “master.” I have some that are sitting in expert 2 and I’m just wondering if I will be tested again to move them into the “master” category, or if I have to do it manually.
No need to manually move an item. 
An item that’s currently Expert 2 will move to Master if you get it correct one more time. You can check when the next review is due on the page for a particular item:
Ooh, cool. Thanks!