Huge crop of Plumbs/too much

My victoria plum trees are so full of fruit that even at this stage with the fruit only about an inch long and green the branches are drooping badly.Should I thin them now o'r will there be a plum drop(pardon the pun) as there is with apples.
I've never had such a big crop so it hasn't been an issue before,they look more like bunches of grapes than plumbs at the moment.Then again I could be greedy and try and prop them up with something I suppose.Plum jam in August me thinks

Thin them by half and the tree will do the rest in due course.

If you don't you will probably lose branches and also find the tree won't crop next year as it will need to recover.

If a tree does crop heavilly it can become a biennial cropper (every 2 years)