Full iPad led to corrupted sync with Dropbox (plus errors in metadata display)

As I started a session, I got an error message saying that my iPad was full (accidentally filled up due to the optimized album downloading full pictures until iPad is full, hard to avoid with 17,000 pics). So I resolved the issue, went back to Scrivener, only to see that the colored chapters no showed no color codes. The colors were still selected in the chapter settings, but didn’t display.

I then discovered a far worse problem: When leaving Scrivener, it synced with Dropbox as usual, and confirmed the save, but when I went to my iPhone version to see how that looked, it hadn’t synced.

After some testing, it turns out that iPhone syncs as normal, and starting new projects on iPhone leads to that project becoming visible in my Dropbox. When I do the same on iPad, nothing happens. But iPad still confirms my saves like all were in order.

In other words: My full iPad seems to have completely corrupted my Scrivener; cannot sync anything with Dropbox, new or old projects. Also doesn’t display color codes, even though they are still selected. Possibly also other errors that I haven’t noticed.

How to fix this?

I could work from my older iPhone sync, but that version is far from recent. I could also transfer the actual chapter text from my iPad to my iPhone using the export function, but then I lose all the iPad metadata for each chapter, plus all my recent research in the Research folder (this can’t be exported, as far as I can see).

I would try to delete my iPad app, but not before I have tried all ways to actually keep what is there, but not in my older iPhone version of my work.