What happened in the French tree?
A couple of years ago or so, I started working on French (from English) and worked up to 1975 XP - Level 9. Because I was planning a trip to Mexico, I switched to Spanish, went off Duo for a while, and then came back to brush up the Spanish and start Norwegian.
I just went back to look at my French tree, and I don't understand what happened. The header shows that I have 30 crowns in French. The first skill shows level 3, and it's red. The next 122 skills show level zero and they're purple. Then I have a couple of skills at level 1, one more purple level zero, and everything else gray. I know I didn't do all of those purple skills. I don't know how on earth I could have done over 120 skills and only accumulated 1975 XP and 30 crowns. I'm sure I didn't make it all the way past the sixth skill test.
Was the tree ripped out and replaced, or did everything just glitch out? Am I basically starting over?
You keep your old (total course) crowns.
There have been multiple tree updates (3 as A/B, CEFR: 8, 12, 13, 14,...).
This has reset (some of) your progress in your tree and a few skills might be set back to the L0 crown level.
More people cried from tree2/3 when they got changed to tree 8/12.
Classic trees vs CEFR trees....so much has changed on tree design and they are not that compatible with each other....so there was some more progress lost when they forced people into them.
I was a little over a year in my French tree when the next day I opened it and went, "What?!!" It was a pretty big shock to have my tree gone, my progress "destroyed" and do go from "over half way done" to "feel like I'm starting over." I felt messed with and I almost quit. It took me a couple of days just keeping my streak alive to realize they had really, really improved the course. They added a ton of content and I had much more to gain from it, rather than just "finishing." I wrote it down somewhere from a discussion (wish I could give it to you) and turns out I lost Tree 3 and was given Tree 12.
To give you an idea of how much more content you have, I now have over 50,000 XP and 98% of that is in lessons, not practice or stories. With all of that time doing lessons, I am still only (ALMOST) half way to a Golden Tree (all skills at level 5). So, there is a LOT of content to chew on.
So, the good news is, welcome back, you have a much better course than you left behind. And you didn't have the Monday, "I am fine," then Tuesday "What the ....?" shock that a lot of us had.
As far as A or B content, I found this. It is a little old, but the post is from AFTER I got my old tree yanked and replaced, so I think the information provides something (probably not all) of what you need about content/complexity/etc.