No surprise here - GM forecast the end of the BB line two years ago due to continuously declining demand, to give their BB customers time to order what they'd need. The Gen V engines (502, 572) haven't been made at Tonawanda for many years anyway - GMPP has them made by outside suppliers, like the ZL-1. The only one Tonawanda made was the 8.1L, and its primary usage was the Kodiak and Top Kick trucks, and those products are now history; the only other users were marine engines.