Me, being me, I kept the parent plant (cut back in summer to try and trigger new growth) and have several cuttings- all dropped leaves during summer as I described.  I scratched the skin on the parent and I think (will check) it was not green.  If so, not a good sign.  All said, because of it's native growing habits, it would surprise me with the care it was given (too much maybe!).  I e-mailed Phil.
It looks like Ireland of later here- not the usual sunshine:-(  Fruit trees all pruned and 2/3 of dormant spraying done (foggy but no rain helps).
Thanks,
Scott