On test server at least it seemed like it would only be possible to get hand on the new demolition buffs by spending gems. It's obvious it has to be a rare buff and even more obvoius it's a dear moment for BB to earn some more $$$ from players buying gems, but even more obvious is the possibility to finally making some sort of use of the worthless saltpeter. I'd never ever build myself a gunpowderhut or what else is in that chain, but if it became possible to turn gunpowder into demolition buffs, say in the new expert provision, I surely would.
The expert provison needs more possibilities anyway to make it worth the effort of implementing, so turning gunpowder into demolition buffs in there would be a very nice start imo.
/AweSumOne