Where does it go?

I have a sawmill set up, and a carpentry as well. I have the sawmill set to store, but every time it hits about 900-1000 litres of planks, they all disappear. any idea where they are going? it's not in line with the time either, so in game hour selling can't be it..

Edit: they spawn on pallets of 1000L nearby, look around the sawmill to make sure