Test Update 4/13/16 - Patch Notes and Discussions

Quick question about the new timer column in the AA window.
What exactly is it timing ? Is it refresh of the AA ? Duration ?

That is telling you what timer the AA is on and what other abilities share the same timer with it just like spells and Disk stacking.

Example Paladin Divine Aura and Bestow Divine Aura are both on timer 72 you can use one or the other.

It shows you what is on the same timer (and thus what shares lockouts).
For example if you go to the Class tab and look at your spires, they will all be on the same timer, so if you use one, you can't use the other two until the timer expires.