The log settled it: the backend was right all along. Every set produced
"readback +1.5s FreqA=21140000 Freq=21140000 -> shown 21140000" and published
cat:state with the new frequency and band. The display did not follow.
The fault is in the frontend. Changing band does two things at once: it opens the
1.5 s freeze that protects what the operator is typing, and it commands the rig.
The rig's answer comes back in ~170 ms — inside that freeze — and the handler
DROPPED any snapshot arriving during it. The backend only emits on change, so
nothing came afterwards, and the strip kept the old frequency until the VFO was
nudged. Changing band from the radio always worked because no freeze was open.
A dropped snapshot is now kept and replayed when the freeze closes, rather than
discarded. Further typing simply defers the replay again.
rouggy
9cfa7a4dd1