We received a "booking information" email from Cunard on February 14th.
IMPORTANT NOTICES
Queen Mary 2 is scheduled to depart from the E Berth Passenger Terminal in Cape Town on Friday, 7th April. Check-in for Queen Mary 2 will take place at the Mount Nelson Hotel, 76 Orange St, Gardens, Cape Town, 8001, South Africa. Guests will then be transferred via shuttle to Queen Mary 2 for embarkation. We look forward to welcoming you on board Queen Mary 2.
It did not show our check in time, but I emailed Cunard to see if the arrival time of our plane (we are coming from Hoedspruit) would be a problem, and was told that our check in is at 1:30.