After 30th of August, Etsy made a significant update to their API and its categories (taxonomies).
In order to be compatible with these updates you'll need to be using at least version at least 2017.02.
After upgrading from an older version of MagetSync - it's necessary to fetch the latest Etsy's taxonomies. This is done from MagetSync Configuration > Listings Manager Options (Left Tab) > Under 'General Configuration' you'll see a button to fetch taxonomies. Click on it and this should update to the latest available Etsy taxonomies.
If at any moment your categories don't match what's on the Etsy website, another taxonomy update is necessary.