I think that it might be a plum, CDF.
The title of this tread caught my eye and I'm thinking, "where would someone be who would be pruning a plum this late." And, there your are - probably right in my part of the world.
I have a peach that has gotten nearly out-of-hand. I pruned it some in early March but the folding ladder just doesn't reach high enuf. So, I'm looking at it now and the buds still haven't quite broken, wondering if I could still do something with that tree.
JONA's response is really encouraging to me and I'm inclined to use the extension ladder to make an effort off the neighbor's fence. I'd better get someone to stay the end of the ladder or I may end up going from one yard to the other, the hard way!
Beyond pruning, I've done just a little "tree shaping." It seems reasonable to me that weighting the branches would work during the spring. But, you'd better wait for someone more knowledgeable to answer your question.
We are each other's harvest; we are each other's business; we are each other's magnitude and bond. ~ Gwendolyn Brooks