First, you don't say if you are raising alfalfa to feed your own cattle, or if you are selling it. 

IF you have cattle to feed, and if you are short on feed - and I presume you are, if you are feeding cattle - consider planting the oats, if/when you get rain.  You can harvest those oats this fall yet as a forage, and the stubble that is left makes a really nice seedbed to no-till the alfalfa into next spring.  IF you do this, you would not have to work the field down again - until you rut it up while harvesting the oats.

IF you are not feeding cattle, but are raising the alfalfa to sell, I might still seed the oats this fall, just to have a cover on it.  Then, again, you can spring no-till seed the alfalfa into the oats stubble.  If you are not going to harvest the oats, I might be inclined to seed the oats a bit later, so you don't get too much topgrowth going into winter. 

Either way, get some kind of cover on the field this fall, when it begins to rain, and look to seed the alfalfa in the spring.