Question
Hello we have a cherry plum tree in the garden and this year as the fruit is growing all of it over the tree is completely distorted and elongated in shape. Over the past years the fruit has been fantastic and the tree itself appears quite healthy.

Answer
Do a google search for plum pockets.  This is a fungal disease that causes the fruit to have that elongate shape and is similar to peach leaf curl in peaches. The plum fruit will have sort of a powdery appearance on the outside.  There are fungicides for control, but at this point it is too late to try them.  Pick off all affected fruit and destroy them as they will be a source for the disease next year.  You may not see the disease next year as it is environmentally driven each year.  I hope this helps a little.  Thanks.