I'm aware of three systems that are used:
1) The in-game clock, which says it is currently Dec 22nd, 2271. This is similar to the Avlis clock, but on Avlis it is currently July 6th, 2249. I believe the clocks have been running off of different ratios since July 9th, 2010, when Avlis switched over to a 3:1 time ratio, instead of the older June 13th, 2005 time ratio of 15:1.
2) The second, simplified, and uncorroborated by any other system, is to use InnRoom time, where one week in RL is equals 1 month IG.
3) And the third system, the one I am specifically trying to sort out here, is the Timeline listed on the Arkaz Wiki. This timeline has not been updated since July 31st, 2011. It last lists the "Yamman Arda portal move" of year 364.
To the best of my knowledge, it is my understanding that Arkaz has it's own reckoning of time, both in terms of it's start date being much younger than Avlis, and that the flow of time itself is less consistent in its rate, being dictated by the plot. This makes the 1st system I listed, absolutely useless.

The second system is interesting, but I doubt accurate to the 3rd. I know that the "Landa and the Dreamcatcher" events of year 363, transpired in Fall 2010, and Winter 2011. If that was in year 363 and we go by Inn Room time, then Arkaz would be somewhere around the year 384.
But if the year is fudged based on plot events, and doesn't adhere to a consistent 4.3:1 ratio, then maintaining updates to the Arkaz Wiki Timeline becomes crucial for anyone attempting to reference the passage of time in their character's life. Presuming some of this information may already be available team-side, would it be possible to have an update made to the Arkaz Wiki Timeline for players to see and make reference to? Failing that, how close does the Inn Room time system come to mirroring the progression of years for Arkaz's story?