> The updater device then sends 64 byte chunks spread over 9 CAN 0x384 frames

Classic CAN uses 8 bytes long frame, so 64 bits. Is it a typo in the post, vor is it using CAN-FD?

I read this as the chunks are 64 bytes and thus each chunk is split over 9 frames. I haven’t looked yet but it’s probably an ISO-TP esque framing protocol.

Must be. Can 1.x and 2.0 are fixed size frames.

Could be TP.DT, multi packet.

My guess is a typo.