Checkpoints on incomplete due to update tree
I happened to notice this by chance and it made completing the easier sections of my newly denuded French tree much less painless.
If you have a previously complete tree, doing a lot of very basic translation to get the easier skills complete is a little dull. On the website, there's nothing for it but to do the lessons or use the workaround to test out individually, BUT... on the app (at least on my iPhone), the checkpoints have reappeared for the parts of the tree where I have incomplete skills.
I just tested out of 2&3, and will attempt 4. The checkpoint tests are relatively long as per usual (I'd say 20-ish questions and three lives), and if you're lingot-poor be aware you won't get rewarded lingots, but it's still a lot faster to test out of skills than to do 50 or 80-odd lessons, which is what I skipped past on the 2nd and 3rd checkpoint respectively.
If you're looking at the new skills and going yay, more content, then never mind, but if you're thinking "But I know this stuff and I don't want to do fistfuls more lessons to regions my tree", get thee to the app and check out the checkpoints.