Blizzard brought up an upcoming change to Chen's trait. Fortifying Brew will grant 25 Brew immediately when Chen starts casting it and 30 Brew per second after that.
The time to reach max Brew is still 2.5 seconds. Front-loading a portion of Brew should make Chen players feel less frustrated when interrupted.
Upcoming Chen Changes (Source)
Hey everyone, just wanted to drop in with an update here!
As I mentioned before, while we aren't really looking to buff Chen, we feel like the Brew-related concerns you've brought up are valid. We agree that it feels bad to have your Trait interrupted when you're low on Brew, almost like a 5-second silence. With that in mind, I'm excited to share that we're going to modify Chen's Trait.
In an upcoming patch, Fortifying Brew will change to grant 25 Brew immediately when Chen starts drinking, and then 30 Brew per second after that (down from 40). It will still take 2.5 seconds to reach max Brew just like before, but with a big chunk of that front-loaded it should be a lot less frustrating when you get interrupted early.
This change is feeling really good in our playtests, and I think it'll be a big quality of life boost for the Brewmaster!
Also, while we're not looking to make large-scale talent updates at this time, we really appreciate all the feedback that's been shared in this thread and will keep it in mind for potential future changes. Thanks again! =)