Conqueror abuse on form switching champs
So normally,
Ranged = 2s Conqueror Melee = 8s Conqueror
Form switching champs however, have access to both. What happens is that if they land a melee form attack, the counter will count down from 8s from when they landed it, giving them 8s to abuse it as a ranged champion (ranged attacks will not reset the counter until the counter is below 2s).
Using Jayce as an example, here's some situations:
Example 1 - Ranged -> Melee: Jayce gets 4 stacks in Cannon form then switches to Hammer for his combo. Afterwards when he E's them away, he switches to Cannon again. He then has 8s to freely use Conqueror in his ranged form without worrying about the stacks falling off every 2 seconds. (more like ~4 seconds honestly, since his melee combo lasts all of ~2 seconds and his R cd is 6 seconds)
Example 2 - Melee -> Ranged (the real problem): Jayce gets a stack(s) in Hammer form then switches to Cannon. For the next 8 seconds, he can stack Conqueror in Cannon form on top of the 8s stack(s) he got from Hammer form (doesn't reset timer unless it goes below 2s). If he switches back to Hammer form and lands an attack before the 8s expire, he refreshes the counter to 8s.
This applies to Nidalee and Elise as well, though only Nidalee has been using it at all between the two.
#TL;DR:
Stack duration should reset and match the duration of the last stack acquired (ranged attacks should set it to 2s, melee to 8s).