Storing Seeds

I keep most of my seed in 30 litre drums, the same ones I store sugar and flour in. I keep in different places depending on the time of the year (coolest spot). There's a lot of work and a large sum of money tied up in what's in those drums, they are on the grab list for bushfire evac. I don't pay a lot of attention to sow by dates, I won't throw seed out unless I'm really pushed for space or have much more than I think I need of that particular variety. I did just do a stocktake and make sure I have some fresh seed (under 24 months old) of everything I grow. I keep everything well labeled and include harvest or purchase date. I also put a plant tag or two into each packet/bag/box, ready for labeling seedling trays or the bed next time they are planted, also as a precaution against someone mixing up inner and outer packets.