Turn Emacs holidays into Org appointments?

[David Rogers]

Hello

I'm using Org-mode to organize readings and music for Christian 
church services. These services are scheduled according to certain 
holidays, and Emacs already "knows" all of the holidays that 
matter for this discussion - they're viewable by selecting the 
appropriate settings for the calendar. (The ones that don't matter 
right now are those that are simply X days or X weeks from the 
important ones.)

I don't currently view or use any of the Emacs holidays as they 
were intended, and I don't really need to.

Is there a way that I can use something like the Emacs holiday 
forms - shown at 
https://www.gnu.org/software/emacs/manual/html_node/emacs/Holiday-Customizing.html 
- but from inside an Org-mode appointment timestamp, so that I can 
use the result in my "Work2022.org" file? Here's a mock example of 
what I'm trying to do:

* Easter
<(holiday-easter-etc 0)>
** stuff for Easter

* The Sunday after Easter
<(holiday-easter-etc 7)>
** stuff for after Easter


This way, there would be less chance for error on my part, and the 
scheduling lines would stay the same from year to year, rather 
than having to look up individual dates and re-write them.

I'd prefer them to show up as appointments and schedules that I 
can modify and rearrange one by one in the scheduling lines of my 
Org files, rather than as a group of holidays that get inserted 
into the agenda from a holidays file - but maybe that just isn't 
how Emacs is set up.

I suppose if I ended up with my own extremely customized holidays 
file, and I added a link in each day's Org subtree to the 
corresponding line in the holidays file, that could be a 
workaround . . .

--
Thanks
David