I consider your implementation of the drastic change to the Free version classless because there was no warning or announcement at all. Even poorer behavior is your website has not yet but updated.
Until now, I used to speak highly of Evernote. Perhaps now I will switch to OneNote. At least Microsoft has the class and courtesy to inform users of changes well in advance.
How to fix this? Consider ‘grandfathering’ current users so they can still use the prior free plan.