Could be a canned answer, but this was from FCA on 12/27/18 when asked about the Gen II blocks listed in the 2018 Mopar catalog:

Thank you for contacting FCA US LLC.

According to available information, part numbers P5160149AC, P5160150AC and P5160151AC are in development and are not available for order at this time. You should remain in contact with the parts department at your local dealership for updates.

Sincerely,
Joe