Decks overwritten or Eases reset - Any way to restore?

For context, I use the Anki app on my desktop and iPhone (and only toggle / suspend cards from the desktop). I just updated to Anki 2.1.44 with the new scheduler on my desktop. After updating, a window popped up saying something along the lines of “your decks are not synchronized – do you want to upload from your computer (overwriting anki web), or download from anki web (overwriting what’s on your computer).” I chose to upload from my computer, and upon starting my reviews, I realized the first few cards (that I unlocked months ago, should have easy = at least 1 month) essentially reset with easy & hard options that were different than I had ever seen.

I’m afraid to keep going through, as I want to change as little as possible until I know exactly what’s going on. Is this an issue with the scheduler update? Or did I somehow overwrite something incorrectly? I think it’s a lost cause if I chose the wrong overwrite option, but has anyone had this issue with the new scheduler? Any help would be appreciated, as it would be incredibly painful to make up six months of med school reviews from scratch.

As I understand it, your most recent progress was on your phone and synced to AnkiWeb. You had an outdated version on your desktop, made some changes to it and then overwrote the data on AnkiWeb with it.
If that’s accurate, you can just sync your phone (upload to AnkiWeb) and then your desktop (download from AnkiWeb). The changes you did on the desktop will be lost through this process.

Generally, if anything goes wrong you can always restore from a backup. However, if you’ve been working one two devices simultaneously without syncing properly and made non-trivial changes, the two states can’t be merged and you have to abandon the progress on one device, as described above.

Perhaps you are looking at new siblings and confusing them with other siblings you previously reviewed? Learning cards show 4 buttons now:

If you believe a card has been scheduled incorrectly, looking it up in the browse screen and checking Cards>Info will show you its review history.