No, I don't think that there will be a permanent enemy force. I think it will be a 1 Bde tasking to supply en force as required. They will be the only ones able to man the TOW's and the Leo's. There will be a permanent staff for evaluation purposes and so on, I think.
It seems to me that 1 Brigade will not be considered a source of more than one BG. They will have sub-units sent on every single roto to every single mission, and that will take a lot of manpower away, and not allow them to train as units effectively. As a matter of fact, if we go to more than two locations with BG size deployments, 1 Brigade will really be hurting to send replacements on the next roto, I would think.
Further, every roto will be spending more time away from home, they will deploy to Wainwright to practice and be assessed before going overseas. This is not necessarily be a bad thing, but because the BG will not be all coming from one location, it will be necessaryto learn to work together before you go. It should be something that all are made aware of, though.