Upgrade Bullseye to Bookworm, and getting of rid of systemd?

[Ottavio Caruso]

Is it at least theoretically possible to upgrade (as opposite to
install from scratch and/or converting Debian to Devuan) stock Debian
Bullseye to Bookworm and getting rid of systemd?

If so, should it be done before of after upgrading? Can one kill two
birds with one stone?

I have found only two references [1] [2] and I don't know how I can
(and if it's worth) putting all the pieces together.

[1] https://wiki.debian.org/Init#Changing_the_init_system_-_on_a_running_system
[2] http://www.chiark.greenend.org.uk/pipermail/debian-init-diversity/2023-April/006028.html

-- 
Ottavio Caruso

A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
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