This seems to be a thing this year, presumably from odd weather we've had. Of my three Pittosporum, one is looking fine, one is looking OK-ish and one (the biggest, sigh) has dropped every single leaf.
Various friends are reporting the same, and a friend went to Wisley this week and they seem to have the same issue.
Does this mean the bald one is a goner, or does anyone have any heartening stories of them coming back? I wonder if I should chop it back in the Spring to give it the best chance?