(How) has the coursework changed over the past several months?

I had to take a break since May-ish, and was wondering if the coursework has changed much, particularly the front-end stuff?

I checked my Map and it still shows that I completed all of the front-end challenges. Does this mean that none of them have been updated?

Bottom-line: as I re-do the challenges, I would prefer to do the most recently updated ones (rather than just repeat what I did 4-5 months ago.)