I think the "timing" is simply due to the ongoing ETC-ETH mess, i.e. "they got lucky". This particular group of scammers were trying to claim some massive hack related to ETC to grab the gullible (ETC debacle will cost a lot of people money, IMO), then just retargeted when they saw a better opportunity and decided to capitalize on the coincidence.

Also, if I was a scammer, I'd just post ambiguous crap like this all the time on a ton of sock puppet twitter accounts. Anyone with any real experience in crypto knows that these kind of hacks happen all the time, so you wouldn't have to wait too long before being able to capitalize on your "foreknowledge" of the event.