Got roped into helping an elderly neighbour pick plums off multiple trees. Definitely didn't have time to do that, but it was really nice chatting with her, she let me pat her hairless cat (!!) and now I have probably 50 pounds of really tasty plums that I need to figure out what to do with (a very good problem to have).
Have you considered using some for a Rumtopf? (Rum Pot) Delicious at Christmas with a little icecream. It is powerful though so only a little and not for children.
Clean and cut the fruit; layer with sugar and strong rum (55%). Use a ceramic container or keep in a dark place. Always make sure the fruit is submerged - use a saucer or plate. If and when you have other summer fruits (berries, stone fruits, apples, pears) add them when they are ripe with more rum and sugar.