[1.1.82] Address already in use when creating a multiplayer game

[thedoh]

I have two instances of Factorio that I use for speedrunning: One dedicated to planning, and one dedicated to running. Prior to 1.1.82 I was able to have both instances running at the same time in a multiplayer setting (with just me joining locally). Since updating to 1.1.82 I am no longer able to do this. I receive an address in use error. The release notice didn't include mention of something like this.

I have attached a sanitised log and screenshot for my settings.