Thanks for that - I wasn't sure whether I should update the existing, older post or not
In answer to your questions:
The error occurs on syncing, not editing. New notes, clipped notes & existing edited notes are all effected. That said, of the last 111 notes, 6 appear to have synced OK - they are all existing notes which were edited since 10/10
Device storage = 59gb/128g available
Evernote not stored on SD card