Engine management can be tricky, especially if you have multiple remotes. With duplicate engines, the best approach is to delete both engines from the remote(s). Next, re-add the first engine to the remote, then with the first engine still on the live track, add the second engine to the remote. If the address is a duplicate, the address on the second engine will change to the next available address.
If you have multiple remotes, you should use the DCS loader program to clone the first remote. If that isn't available, repeat the process. When I've used the app, I generally clear it of engines and add them as I use them.
At AGHR, we have a whiteboard where members post the numbers they're using (including "lash-ups") under TMCC/Legacy and/or DCS so other members don't step on their engine ID's. Members check the board before putting an engine up on the layout. We have tethered TIU on a setup track to add/edit engines without sending an RF signal and potentially grabbing/changing another engine.
