Certified GKH Gardening Expert
Most causes for leaf curl will be treated in Autumn, yes. It will be necessary to pin point the exact cause, though. This could be viral, bacterial, or simply an insect problem. This means that the treatment will vary depending on the exact cause.
This article will get you started: https://www.gardeningknowhow.com/edible/fruits/cherry/cherry-tree-diseases.htm