Old formula powder or leftover water sitting in a formula maker during a move is a recipe for clumps, odor, or worse, so empty and dry it completely first.
Pro tip: Run a plain water flush cycle right before your final use to clear out any residual formula from the internal lines before you even start packing.
Watch out: Leftover formula powder left in a hopper during a move can clump with any residual moisture and is a genuine pest attractant, always empty it fully first.