Yes, it will be updated. OpenVPN AS 2.1.6 was just released, and there's some more stuff on the way, so in a little while, the AWS images will all be updated to the latest version of OS and AS.
To upgrade for example the 2.1.4 AS to version 2.1.6 do this;
SSH to your server
obtain root rights (sudo su for example)
run these 2 commands;
wget
http://swupdate.openvpn.org/as/openvpn-as-2.1.6-Ubuntu16.amd_64.deb
dpkg -i openvpn-as-2.1.6-Ubuntu16.amd_64.deb
If you encounter any problems try a simple reboot/restart first or otherwise contact the support department. You can do so by going to
www.openvpn.net, clicking sign in (if you're not signed in already) and clicking support (at the top of the page) and submitting a ticket and your problem.
