Comment 2 for bug 953621

So, I've checked Gnucash's code and this seems to be a consequence of it using hard links, which are not supported by U1. When you hit save on Gnucash, it will:

1. create a new file (e.g. book.gnucash.tmp-xxxxxx) and writes all your data to it
2. remove the existing file (e.g. book.gnucash)
3. re-create book.gnucash as a hard-link (on OSs that support that) to book.gnucash.tmp-xxxxxx

This has already been reported, though (bug 809370), so I'm marking it as a dupe and will see if I can fix it