A moment ago I was doing timed practice for Greetings1, Greetings2, and the first two lessons of the Days skill. Sadwrn (Saturday) wasn't supposed to come up until the 3rd Days lesson (I think), but when I did the timed practice (before doing lesson 3), it did come up a couple times. I also thought it was strange that the 3rd Days lesson ended with "Creoso, Megan" -- and that when I finished the lesson, it showed that Days had been fully strengthened, but when I left, it wasn't quite there. Did Sadwrn already pop up in one of the other Days lessons (even though lesson 3 lists it as one of the new words), but I forgot? I haven't done Welsh in awhile.
How do you practice the days skill (with or without, timed practice?) if you haven't finished all the lessons?
You cannot specify which lessons you are practicing, just the skill you want to practice. So strengthening the days skill can include any of the words from all three lessons.