Drain Valves Open Or Closed Over Winter

I have winterized my Oakmont with the plumbing antifreeze. I pumped it through to all sinks, taps, toilet, shower and the washer prep. Filled all the p-traps (except the washer drain as it is never used). I also made sure the fresh water inlet and black tank flush had some antifreeze in them as well.

I put about a half gallon down the fresh water line into the tank. Not sure if it needed it or not.

My question is this, do I now open all the drain valves (I have a fresh tank drain, hot water and cold water drain) or just leave all the lines full of antifreeze (I know it sounds like a stupid question, just not sure if the intent of the antifreeze is to flush the water out or if it is meant to keep the lines full all winter).

Also, if anyone has any comments on things to watch for please feel free to post them here. I used the winterization guide here.

Thanks as always.