I have an 09 G10 and a 08 diver both with tritium
Both still glow enough at night be useable
I believe CWC changed to luminova around 2011 / 2012
During the change over they did use T marked dials with luminova on the Quartz divers but I have never seen a G10 with the same (they might be out there though).
Both of the above glow a little brighter for a short time when charged by a light source.
I also have luminova dialed diver with L dial dated 12 so they were definitely marked L after 12.