The 4-layer pack board PR #104 reports DRC 0 errors, 0 unconnected, fab outputs done, but its own review notes quote the Fanstel spec, which says the nRF21540 in BT40X is hardwired to the PCB trace antenna and ANT-SEL is unused. If that holds for the BT40NE, the whip on the u.FL is not driven through the front-end module, which breaks the link budget in audit.py, an ADR, and a body-blocking margin.