Peter, with Evernote support I've find a workaround:
- from web version change temporary default notebook to another
- close and reopen evernote Android, now you can save with success
- from web version change default notebook to preferred
- evernote Android still work normally to original default notebook
If you delete data of app, you have to repeat steps above.
The little problem is that you see default notebook more than one under notebooks, is only grafical issue, app works normally.
I hope that will be fix soon, I'm waiting answer from support.
Ciao