I'm wondering if there is a connection between the mass spam and the recent
newbie mass awaking I'm pretty sure this is the case.
I don't think so, these 90 spam accounts were all pretty new.
In the past, I've often seen Newbies spam with first 35 and later 30 accounts. I'm pretty sure this means someone hired 3 times 30 user spam-packages, and YoBit is probably the only party that has an interest in doing so.
Unfortunately it's impossible to find out who did it, any legit company shouldn't hire spam bots for "marketing".