They've admitted it's a bug and they are fixing it. A note from Evernote support on this:
Our developers are aware of the issue and we are working on releasing a fix for this problem in our next update. Our best option at this time is to wait for that fix. We plan on starting our 10.51 update tomorrow with it taking roughly a week to fully roll out. It could take longer if any issues are found during the rollout.
