Hi Robert,
We want to go a full minute of a wire unplugged or a wireless network hiccup BEFORE we drop the connection.
This behaviour is not entirely controlled by SQL Anywhere. SQL Anywhere relies on the operating system to maintain network sockets from the server back to clients when connected. While connected, SQL Anywhere uses the -tl switch to monitor the connection activity to ensure that TCP/IP connectivity is still there. If the client actually disconnects its socket at the OS level, SQL Anywhere cannot continue communication with the client, even if the network is restored - the network socket is already lost. The server uses the -tl switch to detect this network socket drop on the server-side within a given interval, if it's not already immediately flagged by the operating system when it happens.
When you are doing your testing, are you really only seeing the database client port being dropped in the listing from netstat -a only after the 10 seconds? What database server messages are you seeing in the database server console log?
If I have SQL Anywhere 12 64-bit (latest build) running on a Windows 2012 Server
...
What should we do, and did something regress in SQL Anywhere 12?
I am also going to assume that you were not running earlier versions of SQL Anywhere on Windows 2012 Server. 
You should check out this section of the Windows registry on both the client and server side: http://technet.microsoft.com/en-us/library/cc957548.aspx
Regards,
Jeff Albion
SAP Active Global Support