Resolved! Is the H7 bootloader address still 0x1FF09800 for "V" CPUs?
Revision "V" CPUs use the Version 9 bootloader rather than version 3.1 in "Y". I can't get Jump to bootloader as described in "FAQ: Jump to Bootloader from application on STM32H7 devices" to work on "V" parts although it works perfectly in "Y". As su...