Thanks for the thought.  I actually hide the `addrlocal` field from the output entirely, in the getpeerinfo handler, if it's blank.  If local address is not known yet, the output is unchanged from upstream.

Thought about adding the field anyway but leaving it as an empty string, but that just added bloat to the output.  Using `n/a` instead introduces a magic constant string that conveys no more information than an empty string.