I'm not sure who all is active in the 2142 modding community here on Moddb anymore, and I'm not sure if anyone will even see this, but I figured I'd share anyways. I recently had some free time and an urge to fire up 2142 and my old mod, but I had forgotten about the Gamespy shutdown and realized, to my disappointment, that I could not play... So I fixed it.
I had previously read about the DeathLok clan managing to setup and run their own emulated version of the EA Master Server for 2142, and while that seemed like an adequate fix for the time being I figured it would only be a matter of time before that server goes dark as well. So I did some research into how I might be able to fix the game myself to allow for booting into offline mode (without needing to first disable your internet connection) and after a few attempts I managed to make the necessary edits to the 2142 executable to achieve my goal.
I'm not going to upload my fix just yet as I'm still doing some testing to make sure it is working, but I plan to release here shortly. I will likely upload a new version of the mod that is a complete package so that it is no longer necessary to install the patch and this new version will come bundled with my 2142 offline only fix. I will also upload the fix sperately, because I know it will be useful to people who don't want to play this mod.
I hope that this fix will allow anyone who wants to continue to play this game to do so long into the future! Battle on!
Note: If you want to download the fix immediately, you can check out this thread on Battlefield Singleplayer where I have posted it for testing: