I was lucky, I picked mine (when there was a glut) and froze about 10 years (yes 10 years) ago. Just got enough for another 4 litres.
there was a hell of a lot the year before last as well.
I\'m not so sure that I\'d keep them that long, don\'t forget, stuff does de-hydrate, even in a freezer.
Though as long as you enjoyed the results, what the hell.
Just thinking though, if you\'re here, then you could always just make gallons of sloe gin and sort it. I know that it doesn\'t usually have the alcohol content of mainstream spirits, but I don\'t see any reason why it shouldn\'t "keep".
10 years though, damn! I\'m surprised you managed to chisel them out of the freezer :-D