4/12/18 edit: updated information about IP addresses
A quick update: the previously-planned and then deferred AWS migration for SafeAssign is back on! New date and time are April 2nd starting at 3am EDT. All other information previously provided is still correct.
There was an additional question from the community about whitelisted IP addresses for SafeAssign, and I can confirm that IP address changes will be necessary with this migration. If you have whitelisted IPs for SafeAssign, they should be updated to the values listed here: Cloud FAQs | Blackboard Help
Here is the link to the updated Support Bulletin from Behind the Blackboard: https://blackboard.secure.force.com/btbb_articleview?id=kAA3900000000JTGAY