It looks like the leaves are curling. One of mine does it all the time in the fall. A Japanese grower tells me that "this means it is going to flower a lot next year." It's not doing this at the moment
This is different than
Peach leaf curl which lis a terrible problem.
New ume leaves have red tinged color like that. Check it out in springtime. It's almost completely uninteresting after the flowers have fallen, but that's the color they are.
This should all be completely normal provided the leaves don't get crispy on the tree. I suspect you do have a tough climate to deal with for this tree. Hopefully it will get cold enough to provide it with some weeks of dormancy?
Regards,
Matt