Also adding a bit more from the Part side:
There's a new part for the Gen3 that is listed as:
BLD Tiny8 BTB Type-C card 100W 5C50W00907 - No clue which way the 100W works.
BLD Tiny8 BTB LAN card 5C50W00908 is likely the 2.5GBe card. It is listed as a BTB and 5C50W# which differs from the i350...