I honestly don't know that. They filed 8Ks last year with no 10ks didn't they?
I am not intimately familiar with SEC reporting requirements. I know what the more common forms are, generally when they are due but beyond that I'd have to Google it
Sure they can, nothing stopping them from filing an official statement rather than a tweet, other than Schena's desire to not get caught openly lying, again...one of the reasons 2014-thru today will likely never post too, among others.