If a NG detachment is from a different state than its HQ, does the detachment have to change their Left SSI to the HQ’s State patch?

It depends on the echelon of the state NG unit. For example, if you was assigned to the 34th BCT in Minnesota but your detachment is in another state, then you wear the 34th BCT patch. I hope that this helps but check with your unit commander.

I was in a MEDEVAC Detachment whose parent Co. and BN are based in FL. We wore our state’s default patch.

Then you have other situations where the BN is in one state, a Co sized element is in another state, a detachment of the parent Co is in the same state as the BN, and they all wear the same SSI.

Does the Detachment have a UIC?