Cherry aphid overwinters in egg form on the tree;there's no point in spraying once the leaves have curled over like this - best to spray prior to this happening, earlier in the year. You can also use a plant oil winter tree wash in December, which will reduce the number of overwintering eggs, if your tree isn't too large to spray thoroughly. Further information in the link below

https://www.rhs.org.uk/advice/profile?pid=488

If you can wait, this year is a very good year for ladybirds. One of my apples looks just like your cherry, The lady birds moved in without prompting. The aphids are gone, the leaves are still distorted but that is only cosmetic

I'd be wary of systemic insecticides on cherry, given that the birds eat the cherries.