You don't get a carrier detect pin on the 2.4 GHz devices, so that's one
thing to consider.

You have the ability to get an ACK back from the master, and even to do a
sort of mesh network. "Does anyone hear the master?", then route through
whoever replies, or just fling the packets with source and destination
addresses, and a "time to live" and let everyone repeat anything they hear
that isn't for them, and hasn't expired yet.

Lots of ways to get there.
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