With the lack of much information out there, I thought it would be helpful to put up my armor formulas and WeakAura.
This WeakAura will display your current damage reduction based on your current targets level. Or with no target it will display your physical damage reduction based on a 110 mob.
The Math And Caps
Further the modified here has been based on level, assuming this is still valid, we get the following:
85% Damage Reduction Caps:
110 Mob = 41878
113 Mob = 43020