Thanks for input, friends.
Just cutting off affected parts probably won't help - almost every leaf seems to be affected (!) and I'm afraid that if I regularly nip off ALL the old leaves, the
tree will weaken from the effort of putting out an entirely new set (saw this happen with our white-peach
tree, affected by "peach-leaf curl"...).
Forgot to add that I do see the orange spots develop tiny "volcanoes" that open (a mite? some other bug?).... Feb. could be a bit late for spray, but might try now anyway.
Thanks again!