Sony Artisan Brian Smith commented after the Canon 5Ds launch:
Canon fired the first shot in the Great Mega-Pixel War of 2015, announcing a pair of 50.6 mp Canon 5DS cameras – This is just the first shot! Expect to hear more announcements soon… Who knows, someone might just make a 50mp camera for less than 3700 bucks!
He is likely “hearing” the same rumors I got….sounds exactly like the A7rII to me ;)
Sony has now plenty of time to “fight back” with the A7rII as the Canon 5ds preorders will start on April 30 only at Amazon. And shipment is June/July.