@southjam: See https://winscp.net/eng/docs/rawsettings#sourceaddress

Was this ever implemented, the binding of a specific network interface and if so. How do I use it? I see the tracker, but in the end it does give any details as to if it was implemented or how to use it.

If backed by a donation, I'm pretty sure we will include this to the next major release. A development build can be made available to donors in a short time (few weeks).

Does the issue 416 have a due date?

We may consider to fund it if it helps.

Thanks for your post.

This issue is being tracked already:
Issue 416 – Selection of network interface

Good day. I recently downloaded WinSCP and I am attempting to figure out how I can tell it to use a LAN IP vs another. I have a server with 2 LAN IPs bound to the NIC. I only want WinSCP to communicate through one of those IPs so that we can properly configure NAT rules for external access.

How is this possible?