I live in north TX but have hunted near Fredericksburg for the last 46 years. I know temps there can get pretty low having been there when it was as low as 12.
If I planned to use mine during the winter I would just drain the water heater, drain fresh water tank, drain waste tanks, blow out ALL the lines, and add the pink stuff to all the drains after each trip. 2-3 days at freezing with lows in the teens could damage your water lines. Make sure water is blown from ALL lines including toilet, washer if you have one, outside shower if you have one, black tank flush if you have one.
Since we do not use ours from Nov to March/April I prefer to fill all my lines with antifreeze. But would not do so if I used it several times during the winter.