I've edited NPC in Plane of Time through T9 Old Commons to be 1 level higher than required level to get in. So when you get the new level for new tier, the mobs will con yellow to you. Going back 1 tier they'll con white, and back 2 tiers they'll con blue, etc.
This will probably affect melee, spell resist, and exp gained.
Tier 5-9 have the same exp multiplier value.
Did some testing of AA gained as
solo of being appropriate level for the zone vs being max level and going back a few tiers to farm lower con mobs.
Here are the results without 250% exp clickie:
Tier Level AA Level AA
T5 73 1.87 77 1.34
T6 74 1.92 77 1.38
T7 75 1.97 77 1.42
T8 76 2.03 77 1.62
T9 77 2.08 77 2.08
Here are the results with 250% exp clickie:
Tier Level AA Level AA
T5 73 6.55 77 4.69
T6 74 6.72 77 4.83
T7 75 6.9 77 4.97
T8 76 7.11 77 5.67
T9 77 7.28 77 7.28
Just as on live, it might be worth going back a few tiers to farm blue con mobs for best exp/aa rate per hour, but eventually going back too far would yield green or grey mobs with little or no benefit in exp.
Tiers below T5 have lower exp mod.
The previous npc levels and zone wide exp mods were previously based on players getting max level of 70, but now we're up to level 77 so needed to update the method for npc levels and exp per tier.
Only thing left that would affect AA per hour would be how fast you can kill mobs which is obviously faster rate if you go backwards a few tiers to lower con mobs that have less hp and regen and do less dmg to you.