You will need to drain the filter separately. Be carfel not to "spill" when unscrewing the jar. I don't really have room to put much of a pan under it when unscrewing it, and the area below it is an area that they ran carpet to, so I have to be VERY careful. I then bypass the filter by disconnecting the lines going to either side of it, and connecting them together with a plastic double male that I picked up at the local hardware store.
Then when I pump the pink-stuff through the system, I'm not using half a gallon to fill the filter jar, plus I don't have to worry about spilling again in the Spring. I've heard of others that fill the jar with washed stone or marbles to minimize using the extra anti-freeze, but for me, it's just easier to bypass.
In the Spring, I may buy the three valves and the fittings that I'd need to plumb a bypass on the filter, but that's a low priority project.
2014 RAM 2500 Laramie 4x4 Quad Cab w/Cummins Turbo Diesel, 2009 Rockwood 2607, and 3 'yaks!
300W of Suntech Solar, a Rogue MPT-3024 Controller, and a Xantrex PW2000 Inverter