Back ordered until....
Whatever you ordered is OBSOLETE...MuHAHAHAHAHAHA.
Or my personal favorite.
Back ordered until I no longer NEED IT! Because I CRACKED under the pressure ANDBOUGHTWHATEVERWASONTHESHELFATTHETIMEEVENTHOUGHI TMIGHTNOTWORKBUTICANMAKEITFITPLEASETAKEMYMONEYBEFO REISWALLOWMYTONGUE!!!!!!!
Very Common for an O.C. Nut like myself!