Felhunter running after targets to spell lock

I've noticed that my Felhunter, upon trying casting Spell Lock, will chase the target and cast it as soon as it is in range (30y).
This is super annoying as Spell Lock usually pops way too late, wasting the CD.

This happens on Lordaeron but NOT on Ragnaros, where I get a "your pet is out of range" error instead.
I submitted a bug report and got promptly dismissed as "Nothing wrong with this behaviour", although it seems very wrong to me, especially after playing on Ragnaros with years without the issue.

It's hard to find the actual retail behaviour, not easy to Google this... can someone enlighten me please?

EDIT: dismissed bug report here https://www.warmane.com/bugtracker/report/18015

Nevermind, found this http://www.arenajunkies.com/topic/17...lock-question/

Lordaeron behaviour seems good... it's Rag which is bugged