OK - I now understand that the 23.05 Armbian release for my arm64 hardware may be skipped altogether, in favour of a 23.08 release.
So, I am placing my hopes on seeing an upgrade from the current 23.08 trunk to 23.08 stable on my system sometime soon.
And then, at some point, upgrade from Bullseye to Bookworm as Patrick Zajda has already done
I see Patrick is on an N2+, but I'm guessing the upgrading processes for Odroid C2 and N2+ are similar, if not identical.
Antipode got a reaction from Patrick Zajda in Upgrading from 23.02 to 23.05