We've been contacted twice now by someone claiming to be from Blackboard. They are saying that we are owed a refund, but their registration system has changed and they will need the entire credit card number that we used to register in order to execute the refund.
The number that has called us is 866-377-2421, and this is obviously a scam. We asked for a revised invoice to be sent to us and they just hang up.
Stay vigilant, everyone.