I have a stuff sack that I attach to the top of the of my BOB. The basics of the contents stay the same. Food gets rotated and things get updated according to how fat I get. In the summer, the stuff sack comes off. In the winter, the sack with fleece and gortex, hat, gloves, tinted goggles and heavy socks (extra pr.) gets attached to the BOB again. I works well for me.

I have a monster fannie pack that I update according to the day. It gets stuffed in my jeep for EDC.