Earlier today, Samsung uploaded a new version of the Galaxy A3 (2016) user manual to its Download Center. Based on initial impressions, it would appear that the support booklet has been revised to include instructions on how to use the new functionality baked into Android 6.0.1, indicating that a Marshmallow rollout for the handset is right around the corner.
Unfortunately, it's still unclear when exactly Samsung will start pushing the firmware to the device. However, it usually tends to do so within a couple of days of publishing an upgraded user manual — so if you own a Galaxy A3 (2016), you shouldn't have too much longer to wait before you can start taking advantage of an upgraded version of Smart Lock, a redesigned App Drawer and enhanced battery life through Doze.