Here's how to specify IP Bindings when you have both IPv4 and IPv6 addresses. The format is ...
[2907:f0d0:1f01:13b::17] 199.47.66.196
... where addresses are separated by spaces and IPv6 addresses are enclosed in brackets.
Took me a few minutes to figure out this out, so posting it here for others. If you get things wrong, FileZilla Server reverts to * (all addresses).
FileZilla Server IPv6 IP Bindings
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