Does anyone know how I go about switching from NG Infantry Officer to Reserves Civil Affairs/MISO?

Yes, email me at [login to see]

I would recommend that you get more time in your basic branch, but...
First, you'll need to find a CA or MISO unit willing to accept a 2LT. Most are critically short of company grade officers, but it will take waiting a while or a bunch of waivers to send you to the CAQC as a 2LT. Not all units want to wait that long or jump through the hoops.

With a para/lin in hand, complete a conditional release from the Guard. That'll be processed through your current CoC.
When that is done, go to a Career Counselor and swear in as a Federally commissioned officer.
Lastly, you'll complete the release and discharge from the Guard and acquisition to the USAR.

Once that's done, you have some work to do to get qualified.
Feel free to message me directly if you have technical questions about the process or just want general information about CA. You'd be hard-pressed to stump me; I've been doing this a while.

Hi Sir,
In addition to COL (Join to see), you can also reach out to COL Douglas Hurst and/or BG (Join to see) via RP. All three have been extremely responsive and helpful in offering guidance to officers looking to make the switch in the past.

MAJ Laurie H.