After spending a few months away, I got home to a most of my trees being fine. unfortunately, three trees left me. Two of my olives were stored in the greenhouse. And without properly informing my caretaker the olives were not watered when the sun came through in early spring.
One other tree, my decades old Tamarix unfortunately also died. It is completely unclear to me why. If I had to guess I would say the 15 degrees of frost in mid March were too much, with a tree already out of dormancy!