Is it possible to mix kills from normal and heroic BRF to get a heroic BRF cache?

[Garrior]

Since it is said that you need 21 kills on a certain difficulty in BRF to get the cache with loot from the next difficulty, I wanted to know if it's possible to mix kills from normal and heroic to get a heroic cache.
Like for example: you have 10 kills on normal and 11 kills on heroic. Would you still get the normal cache or does that count like 21 normal kills so you can get the heroic cache?

[Reyzzz]

afaik, heroic brf kills count towards mythic brf cache, not the heroic one.

[Count Zero]

My understanding is it's "that difficulty or higher".

So, yes, unless my understanding is wrong - normal, heroic, and even mythic kills should count towards getting a heroic cache.

[Mollaroo]

My understanding is it's "that difficulty or higher".

So, yes, unless my understanding is wrong - normal, heroic, and even mythic kills should count towards getting a heroic cache.

That is NOT the way it worked for Highmaul--that one was specifically kills on a particular level, so 14 normal + 14 heroic + 6 mythic = a normal cache. It may or may not have been changed for BRF, I have no idea.