Question about Kalista

I thought her E was supposed to refund mana after killing one unit? It still says on her e if you read the description that if you kill two minions it refunds mana. And while i was killing minions with my E if i didnt kill 2 it wouldnt refund the mana.

This is what her E says on the patch notes

E - Rend STACKS ON STACKS Basic attacks and Q - Pierce add a spear to enemies while Rend is off cooldown ⇒ at all times MANA REFUND 2 units killed ⇒ 1 unit killed (matching the cooldown refund requirement) BUGFIX Fixed an issue where Rend’s cooldown sometimes didn't reset when Rend killed a unit

This is what it says when hovering over Kalista's e

Active: Rip the spears from nearby targets, dealing 20/30/40/50/60 (+60% Attack Damage) physical damage and slowing their Movement Speed by 25/30/35/40/45% for 2 seconds.If Rend kills at least one target, its cooldown is reset.If Rend kills two or more targets, its mana cost is refunded.