If not, you'd be well advised to get with the Program as it is time to Get Squared Away. You can test your domain here at DNS Flag Day, or educate those always hungry neurons here. All of this fal-de-rol is slated to be accomplished worldwide on or about 2019/02/01.
"The current DNS is unnecessarily slow and inefficient because of efforts to accommodate a few DNS systems that are not in compliance with DNS standards established two decades ago. To ensure further sustainability of the system it is time to end these accommodations and remediate the non-compliant systems. This change will make most DNS operations slightly more efficient, and also allow operators to deploy new functionality, including new mechanisms to protect against DDoS attacks." - via DNS Flag Day