Band and frequency have to agree — the log, every award and every upload
are read on the BAND — and an operator fixing a wrong frequency is not
also expecting to fix the band by hand. That is exactly how a QSO ends
up filed on 20m at 7 MHz. Both sides follow, TX and RX.
Only when the number lands in a known allocation, because half a
frequency is typed on the way to all of it and a band must never be
blanked by that. bandForMHz moves out of App.tsx into lib/bandplan,
where the two callers can share one answer instead of drifting.
rouggy
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