“Hearses at Daybreak”: How a Tolkien birthday card has made the rounds on the Internet

It is always wonderful to find a decent birthday invitation card. It adds both style and the opportunity to make a very good point – of how the birthday is going to go.
This holds true with a card for a very special person, in this case for:
Sub.-Lieut. C.J.R. Tolkien, R.N.V.R.
And his Coming of Age on Nov 21st, 1945.
There is so much in this invitation.
First of all, this is after the Second World War ended. So Sub-Lieutenant Tolkien of the Royal Naval Volunteer Reserve (RNVR) would be celebrating his birthday without the sword of Damokles, that is, war, hanging over his head.
Second, it is his coming of age: Christopher Tolkien turned 21, knowing full well, that he would be able to continue his studies, in this case reading English at Trinity College, Oxford, in 1946, to receive his B.A. in 1949.
Thirdly, the lines at the bottom turn this into one of the most hilarious cards ever:
Carriages at midnight. Ambulances at 2 a.m.
Wheelbarrows at 5 a.m. Hearsed at daybreak.
Oh, and you only needed to RSVP if you were NOT coming.
Oh (part 2): Yes, there is this line in The Lord of the Rings.
About midnight carriages came for the important folk. One by one they rolled away, filled with full but very unsatisfied hobbits. Gardeners came by arrangement, and removed in wheel-barrows those that had inadvertently remained behind. [Book I, Chapter 1, A Long-expected Party.]
Tolkien wrote this in December 1937 and/ or January 1938 as this was the time he started on the “new Hobbit“. Given the fact that Christopher was his father’s confidant on the novel, reading it in serial form over the next few years, I am sure he will have even more appreciated the joke.
But why am I mentioning this? Well, the image of this invitation started making the rounds on July 16, 2020 (TinEye search). It comes as no surprise because it was included in John Garth’s Worlds of Tolkien (published June 9, 2020). So someone scanned it from the book and put it on imgur. From there it rapidly spread and has been shared mostly on Christopher’s birthday.
Neil Anderson was so kind as to let me know that this invitation had been published elsewhere: In Wheelbarrows at Dawn (the title is a give-away) and later on in The Great Tales Never End: Essays in Memory of Christopher Tolkien that was published in June 2022.